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Demco Stay-IN-Play Duo Flat Tow Brake System for RVs w/ Hydraulic Brakes - Proportional

Demco Stay-IN-Play Duo Flat Tow Brake System for RVs w/ Hydraulic Brakes - Proportional

Item # SM99251
Our Price: $1,175.00
You Save: $493.98
Tow Bar Braking Systems

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Plug in and go: this permanent system gets you smooth, reliable braking with a one-and-done installation. Low-profile components designed to stay out of sight. Great Prices for the best tow bar braking systems from Demco. Demco Stay-IN-Play Duo Flat Tow Brake System for RVs w/ Hydraulic Brakes - Proportional part number SM99251 can be ordered online at or call 1-800-940-8924 for expert service.
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Demco Tow Bar Braking Systems - SM99251

  • Brake Systems
  • Hydraulic Brakes
  • Proportional System
  • Demco
  • Fixed System
  • Power Assist Brake Compatible
  • One Time Set-Up

Plug in and go: this permanent system gets you smooth, reliable braking with a one-and-done installation. Low-profile components designed to stay out of sight.


  • Guarantees smooth, reliable braking
    • Reads RV's brake light signal to ensure system only activates when you actually hit the brakes
    • Senses the rate of your RV's deceleration and triggers your towed car's brakes to slow down at the same rate
    • Lets you adjust braking sensitivity to suit your vehicle and your preference
  • Plug-and-play
    • System automatically turns on when your towed car is connected to the RV
    • Components install permanently and stay tucked out of sight
  • Monitors your towed car's braking with LED indicator on car's dash
    • Lights up when the brakes are applied
  • Avoids damage from over-braking by reactivating car's vacuum-assisted braking
  • Includes breakaway system and all necessary components
  • Made in the USA


  • Application: motorhomes with hydraulic brakes
  • Compatible with hybrids and other cars with continuous-power-assist brakes
  • Operating unit dimensions: 8" long x 5" wide x 2-1/4" tall
  • 5-Year warranty

stay n play duo review

"This is the top system I recommend if you have hydraulic brakes. Quality, reliable, tried-and-true. It just always works."

Do I Need a Braking System for Flat Towing?

A braking system is a must when towing a vehicle behind your motorhome. Without it, the weight of the towed car can create a safety hazard, strain your RV's brakes, and affect the warranty of both your car and motorhome. Most states legally require a supplemental braking system, so if you don't use one and you end up in an accident (which is more likely since your RV takes longer to come to a full stop), your insurance and liability headache just doubled. You also won't have any breakaway system; if there's an accidental disconnect, there's nothing to bring your car to a stop.

Pros of a Permanent System

The Stay-IN-Play Duo is a permanent braking system, which means that it's a one-and-done. Once it's installed, there's no more setup that you have to do. When you plug in the power cord at the front of your vehicle, the system automatically turns on. Flip the on switch for the G-Force controller and just like that, you're ready to flat tow.

While the components are installed permanently in your RV and toad, they remain concealed and inconspicuous. None of them will interfere with normal driving, and most of the time they are invisible. And you don't have to find a place to store them between trips.

How Does the Demco Stay-IN-Play Duo Work?

The Stay-IN-Play Duo is unique in that it uses both an inertia sensor and your motorhome's brake light signal to activate. Having this double-check ensures that the system will only activate when it's truly needed.

Demco Stay n Play Duo operating unit

First, the Duo monitors your motorhome's brake light signal so that it knows when you're intentionally hitting the brakes. This ensures there's no false braking.

Second, the inertia sensor in the Duo senses the change in momentum of your toad (towed vehicle) as your setup slows down. It precisely measures this change so it can activate your toad's brakes to match the rate of the RV's deceleration; this is what makes it proportional. When you apply the brakes in your motorhome, the braking system will engage the brakes of the toad at the same time with the same amount of force. This keeps the RV and the toad in sync with each other, so whether it's a gradual slow down to a red light or a hard stop in an emergency, the toad and the RV will brake together.

Demco G Force Controller

It starts with the G-Force controller. The G-Force controller contains the inertia sensor that senses the change in your RV's momentum. You'll install it in the cab of your toad, underneath the dashboard. This keeps it out of the way but easy to reach so you can flip the toggle and adjust the knob.

Note: The G-Force controller must be pointed in the direction of travel - with the toggle switch facing the driver's seat - for the internal sensor to function properly.

The controller lets you adjust the sensitivity of the inertia sensor to determine how drastic the change in momentum must be for the system to trigger. Set the sensitivity low and the Duo will only engage when you forcibly step on your motorhome's brake pedal. Set it high and a mere tap on the brakes will get a reaction. It's totally up to you how sensitive you want it to be; a heavier vehicle will probably need more sensitivity, while a lighter one doesn't need to brake so hard. The knob on the face of the controller lets you easily program your setting.

Demco Stay n Play Duo operating unit

When the G-Force controller detects a change in inertia, it checks that there's a brake light signal from the RV to confirm that it is indeed braking. It then sends a signal to the main operating unit to activate; the main unit delivers pressurized air through an air line to the actuating cylinder that attaches to your toad's brake pedal. The cylinder will pull the pedal down, applying your brakes almost instantaneously.

Demco Stay n Play Duo cylinder mounted on the brake pedal

The actuating cylinder attaches permanently to the arm of your toad's brake pedal. Though it is permanent, it should not interfere with your everyday driving. In most vehicles, it is tucked up where you can't even see it.

Vacuum Pressure Creates Smooth Braking

When you're driving, your vehicle uses vacuum pressure to create the force needed to bring the car to a stop. On most vehicles, this vacuum-assist function does not work when the engine is off. As a result, a lot of supplemental braking systems have to use an excessive amount of pressure while braking the toad.

The Duo, on the other hand, reactivates the vacuum-assist function by tying into your car's vacuum line. Your car will brake evenly and naturally as it's being towed, so there's less risk of damage.

Built-In Safety Features

Demco braking monitor

Included with the Duo is an LED indicator light for safety and peace of mind. This LED, mounted in the toad (on the dash or on the back of the rearview mirror) and visible in your RV's backup camera, will light up whenever your toad is actively braking. It's a simple way to keep tabs on whether the system is working properly or if something is going wrong.

Most supplemental braking systems have a method of letting you know you when they activate, but not all of them are checking if the toad is actually braking. There could be an error that causes the system to activate without actually applying the toad's brakes. Or your brake pedal might actually be continuously depressed when it shouldn't be. But unless you have a system that's monitoring your vehicle, you won't know it until the damage is already done.

This braking monitor connects directly to your toad's brake light switch so it only lights up when the pedal is depressed and a signal is sent to the brake lights.

If there's a strong glare on your toad's windshield, the LED light strip might be hard to see. The wireless Coachlink system (SM99945 - sold separately) is a great solution to this problem; the monitor mounts right on your motorhome's dashboard so it's directly in view. This is a great add-on for convenience and peace of mind.

Demco break away switch

The Duo also comes with a breakaway switch, an absolute must for safe flat towing. If there's ever an emergency situation where your toad becomes detached from the motorhome, the breakaway switch will immediately activate the brakes and bring the vehicle to a stop.

This switch mounts to the front of your toad and wires into the Duo's operating unit. It includes a pin that connects to your RV's hitch receiver with a breakaway cable. If the toad and RV become disconnected, the cable will pull the pin out of the switch and trigger the braking system. A reserve air supply in the operating unit will then apply the brakes in the car.

What You Need to Flat Tow

Flat towing can be a much more convenient way to take your car RVing with you than using a trailer or a tow dolly. It'll save you storage space both at home and at the campsite, and it takes less time and hassle to hook up.

To flat tow your vehicle, there are 5 basic components you're going to need: a tow bar, a base plate kit, a safety cable set, tow bar wiring, and a flat tow braking system.

For the RV Between the RV and Towed Car For the Towed Car
Hitch Tow bar Base plate
Wiring plug Safety cables Braking system
Wiring adapter cord Wiring kit/diodes

The custom-fit base plate installs on the frame of your toad so you can connect the car to your RV with a tow bar. Hook up safety cables between the vehicles to ensure that the toad does not separate from the motorhome if the tow bar becomes detached. Tow bar wiring syncs your vehicle's signal lights with your motorhome's tail lights, as required by law in most states. Finally, the flat tow braking system - also required in most states - activates the brakes in the toad when you hit the brakes in the RV, making for smoother, safer braking, and preventing wear on your motorhome.

9599006 Demco SBS - (Formerly SMI) Stay and Play DUO Supplemental Braking System for Motorhomes with Hydraulic Brakes - Proportional

Replaces Demco SBS SM99251


Installation Details SM99251 Installation instructions

This Product Fits The Following Vehicles

Customer Satisfaction Score:

Customer Reviews

Demco Stay-IN-Play Duo Flat Tow Brake System for RVs w/ Hydraulic Brakes - Proportional - SM99251

Average Customer Rating:  4.8 out of 5 stars   (564 Customer Reviews)

Plug in and go: this permanent system gets you smooth, reliable braking with a one-and-done installation. Low-profile components designed to stay out of sight.

2017 Chevrolet Spark

I mounted this in a 2014 Chevy Spark. Finding a spot for the main control unit was interesting, but I found a video for a 2017 Spark that I could use. I did have to drill an extra hole in the mounting flange and car. I haven't taken it on a trip as of this time, but a tow around the block indicated it was working. One note, watch about placing the LED indicator behind the tinted part of the toad window. It makes it harder to see from the camper camera.



We are very pleased with this system. We hauled the Spark on a 5,000+ mile trip out west and the brake system did its job. I did tweak the setting a couple of times to get it as I liked it. As noted in my initial post, I still have trouble seeing the LED indicator behind the tint if the windshield, especially in bright sunlight.

2020 Ram ProMaster 3500

Installing on 2020 Jeep Trailhawk :

Pic #0557 : Roadmaster Base Plate Kit , Demco Supplemental Braking System , Diode Wiring Kit , Demco Battery Charge Wire Kit

Pic # 0548 ,0551 , 0559 Had to adjust the bracket plate to line up with the upper bolt holes

Pic #6028 finished install , mounted the operating unit to the top fuse box cover using automotive Velcro . Air cylinder , controller and LED light installed . Aside from the base plate bracket not lining up with the upper bolt holes I would give it 4 stars . My son in law is a master at solving mechanical issues .


The Demco stay-n-play braking system has worked flawlessly for a full season of towing! The one time installation went smoothly and all components fit and functioned perfectly.
Very easy to use, connect to tow vehicle, flip a switch, and it's ready to tow. Disconnect from tow vehicle, flip a switch, it's ready for normal driving.
Would highly recommend this setup over other braking systems.


Installed on a 2013 Nissan Frontier. Works great but I had a hard time finding someone to install it. I tried my regular mechanic and an two others. They did not not want the liability? The Demco site lead me to an RV service shop that did a great job. They hide the wire from the brake indicator mounted on the rear view mirror by routing it through the trim so it just stays plugged in (one less thing to do when hooking up). They also added a battery charging line from the motor home to keep the Frontier's battery from getting too low from exercising the brake on long trips.

2005 Jeep Liberty

I'm very pleased with this Stay-in-Play /DUO Braking System which I installed on my 2005 Jeep Liberty. I debated wheather I dared install it myself, but with the video instructions I decided that I could. I watched the video a couple of times, then followed it step by step during the installation, and it went pretty smoothly. One issue I had is that they changed the instalation of the LED indecator light, since the making of the video, so the parts did not come as described on the video. I do prefer the new method, as described in the installation manual, but it does require a toggle switch to turn it off. I installed one just below the Control Unit inside the car (see photo). I was also very impressed since, right after ordering the system, I found it for less on another web site. I emailed eTrailer about my disappointing discovery, and they credited me back the difference. GREAT COMPANY!

Robert P.


One year later, the system is still working great. Still very pleased.

2016 Ford Edge

Thanks to installation videos provided by etrailer, I felt confident that I could do the install myself. I had never pulled off moldings and panels in a car before, but with your videos as guidance , it was a breeze. This system was going into a 2016 Ford Edge 3.5L AWD and your (and SMI's) instructions call for installation of 2 check valves. After calling SMI to clarify the install points, it got even easier, as only one valve is required, and is ridiculously simple to install it. No cutting of original car hoses required (see photo). After everything was installed, the whole setup just simply worked, no troubleshooting required. That was fun and it is totally doable, even for the average guy like myself.

Herbert M.


The rear-view camera display in my RV is not good enough to show the operation of the brake notification LED which is applied to the rear-view mirror in the towed car. I installed a small light in the RV dash and ran wiring all the way back to the toad, with a disconnect plug at the hitch, of course. Now it is easy to see when the car brakes come on. Else, the system works great.


Haven't actually had the chance to tow behind yet so this is just for the install. It took me quite a long time to install but, that's not the products fault. Everything you need to do the job is included.
I only give it 4 stars because the system uses the towed vehicles battery to activate the vacuum/compressor pump, so it would be possible to run the battery down as there is no charge circuit from the towing vehicle. I did choose to add one though. Other than that I'm sure it'll work fine. It was installed on a 1983 Vanagon.



Im not in the car when it works, but the indicator light comes on so I assume they work. Honestly, my motorhome is so big I cant tell if there working or not, mostly I stalled to be legal and safe. I like it.

2020 Jeep Wrangler

Absolutely great product and worth the time and effort to install. Once installed and "adjusted correctly" this unit is flawless. I installed it with everything else from ETrailer in 3 days, taking my time and I have a very clean installation. Once installed the tech support guided my "sensitivity" level for the perfect application. Also their TECH support was on it both times I called. The other was in ref to a brake light switch sold by etrailer but was not needed for this and they provided the intel off the top of his head. Absolutely recommend this product and both DUO and Etrailer as companies.

2014 Honda CR-V

After watching the excellent installation video I had very little trouble installing this product. I like the fact that it is a stay-in-play system that literally requires only the flip of a switch to activate. The major components are all installed out of the way, yet are still easily accessible. As for the braking system itself, I find it operationally excellent and believe this product choice was a great one.


Best braking system om the market and e trailer once again is the best value for your dollar. been using the system for over a year without any issues what so ever


I am very deceived and feel I have bee fooled by the false affirmation, this is not proportional. I DO NOT RECOMEND THIS PRODUCT.
This system is nothing but proportional. All proportional wording or video is misleading should be removed. It's actually an on-off system. When braking light is on and the tilt sensor actually (on-off) is on the pump is on at full pressure pressing the brake until it bottoms out, period. The pump inlet creates a vacuum for the brake booster and the pump outlet is for the cylinder pressing the brake. All triggered by a simple switch. Nothing is regulated or proportionally controlled. Totally false information is provided here. Unfortunately the initial concept is good, but lacking the extra electronic pressure regulator and electronic control.
I had to set the angle switch so the system ONLY TURNS ON in the event of an emergency, otherwise it will brake fully and destroy your towed vehicle brake.
I am sure this review will not appear and will be deleted by the moderator. Too many good fake reviews...

Etrailer Expert

Brooke M.


I reached out to the manufacturer about this and they said what makes it proportional is the system works on two signals, the first signal needed is the brake signal that comes electrically from the coach, the second signal is when the towed vehicle feels forward inertia. The pump does not come on full, it slowly ramps up pressure, the more inertia felt the longer the system runs, the longer the system runs the more pressure that the system creates. The more pressure the system creates the harder the brake pedal is depressed. I also asked about the sensitivity issues you seem to be having and Demco said they have heard of that before when the sensor isn't installed level, as outlined on page nine of the instructions.


Works great! I would buy it again. Tow a 2021 Jeep Wrangler, 5400 lb., And glad to have the braking help, especially in the mountains. Low maintenance, no complicated wiring between motorhome and Jeep.



Still working great. Simple to use and effective. I have recommended it to many fellow RVers.

2003 Subaru Outback Wagon

I chose to go with this unit because I didn't like the idea of the other types that mash the brake pedal without any vacuum assist & the fact that you have to remove, then reinstall them each time you want to use the car.
This ended up TOUGH install. Not because of the unit, but rather the lack of ANY room under the hood on my 2003 Subaru Outback Wagon to mount the operating unit. The only place I could find that would be out of the way was under the driver's seat of all places! Luckily there was JUST enough hose with the unit to reach all the way to the brake booster. I had to cut the carpeting so the seat would clear the operating unit during movement without any chance of contact. There was no hole in the firewall large enough to accommodate the hose so I had to drill a hole for that although I was able to route the wiring through a small rubber grommet. Routing the hose to the firewall was a real challenge! I ended up running it through the heater duct under the driver's floor mat to the left side kick panel, then up over the pedals keeping clear of any moving parts. WHEW!!
The brake pedal actuator went on without much fuss, although with my large feet I have noticed I'll catch the actuator with my toe on occasion. I may mark the location it's in now & merely raise it up a tab in between trips.
The wiring was pretty much straight forward, there was plenty of included wire & I had JUST enough room tho mount the G-Force Controller on the left kick panel covering without interfering with my feet.
The breakaway switch I fastened to the body in front & below the radiator.
I read where everyone was saying you need to have a battery cut-off device to keep the braking system from draining the battery over time, but I had power from the RV keeping the battery fresh so I didn't worry about that & saved myself the $180 for the cost of an automatic battery disconnect.
After installation, I sat in the car while we towed it around the neighborhood to see how it worked & made the necessary adjustments to the G-Force Controller. Now THAT was weird! What with the car steering itself & braking too.
We just got back from a 4,000+ mile trip & everything worked fine. On occasion I forgot to flip the switch to turn the system off, but it didn't seem to make much of a difference.
All in all a great system!


Works very well it saved my Jeep from a bad accident, but it will run down your battery, I use a solar panel on the hood to keep the battery topped off.


Braking system is easy to use and works great. System was installed by etrailer and they did excellent job.


It wasn't easy to get everything installed in a way that looked neat and professional but in the end the ease with which you can hook up the car and start towing makes it worth it. I bought a replacement factory vacuum pump line so that I didn't have to worry about ruining the original one and as a result the installation looks that much better. Literally all I have to do is flip a switch once the car is connected and I'm ready to go. Given a second opportunity to do the installation I would mount the LED light strip vertically on the backside of the rear view mirror to make it a bit more visible but other than that, I'm happy with how it turned out and the system works great.


The stay in play system has worked perfect for the last 8000 miles, I am very satisfied .


I personally installed this on my 2020 Jeep Wrangler and have towed it using this braking system over 4K miles and have had zero issues. Would definitely recommend! The installation instructions were well written and included an easy to read wiring diagram making is easy to install and the very knowledgeable etrailer support was a bonus too!


Erica G at etrailer was very helpful with managing my order and getting it to me w/ regular updates. The installation takes a lot longer than all of the etrailer 30 min videos but after it’s installed it’s easy to activate.

2019 Jeep Wrangler

great kit for installing a supplemental braking system in my 2019 jeep wrangler. It takes several hours to install, but if you follow the instructions and watch the video, it's a pretty straight forward install. Just think it through and plan where you'll route the wiring and hoses. The hardest part was being flexable enough to mount the hardware to the firewall behind the brake pedal, but that's not a fault of the system.

2018 Jeep Wrangler

After doing much research and reading many reviews and watching a lot of your instructional videos I chose the Stay-in-Play Duo. It came complete with instructions and extra parts for any application. I like the fact that after everything is installed it is just a matter of flipping a switch and checking it out and drive off. I mounted it in a 2018 Jeep wrangler, not very much room for the operating unit, but I I went off of one of your videos on a 2017 Jeep Wrangler Unlimited and mounted it underneath above the cross frame below and behind the radiator but still protected from the elements. Not a lot of room under the dash either, but everything is in and looks great and ready for the 1st trip.

2012 Dodge Charger

I installed this in a 2012 mini Cooper S. With the turbo charger there is no room in the engine compartment for the system unit, so I mounted it under the passenger seat. I had to remove the seat, cut out the carpet, mount the unit, and then buy longer seat attachment bolts. I used half inch thick spacers between the seat track in the floorboard. Made a long run for the vacuum hose to get up to the engine compartment through the firewall. By removing the cowling on the driver side, it exposes a huge Gromit where the main wiring harness passes through the firewall. It actually had two nipples ready to be cut off to run the vacuum hose and the wires through — so that part was pretty easy.
I haven’t towed it behind the motorhome yet, but it passed all the start up tests the first time!

2013 Jeep Wrangler Unlimited

Just towed for the first time using this system. Worked great on our Jeep. Now we just flip the toggle switch to turn on and off. Install was a bit of a challenge, but the Demco help line was very helpful.


As always, E-Trailer is a class act. Excellent products and excellent service before and after the sale. I wish all companies would emulate E-Trailer.

2015 Jeep Wrangler

SMI Stay in Play Duo installation in 2015 Jeep Wrangler Unlimited –
Packaging was great with everything needed included plus extra items for various installation methods of you’re choosing. Upon initial investigation and survey, everything except the CD Information pack was accounted for.
No big deal, as I had previously watched 2 different Youtube installations found on the internet. In fact, the internet videos were what I used as my step by step installation process, and the written instructions were only used for concerns where the video may not have been as clear as I had hoped for.
Understanding that everyone has their own style and methods for doing this project, I purposely was not in a hurry to rush through it. All in all, I took @ 8 hours to install the Adapter 4 to 6 pole #30637, the EZMount Tow lights Kit, and the Stay in Play Duo Braking System.
I choose the EZMount because I didn’t want to mess around with the OEM taillights and wiring. Magnetic lights don’t work so well on composite tops and I didn’t want to stick them to the sides of te Jeep, so I modified the EZ mount to wrap around the thickness of the rear glass hatch on both sides. I added a 2”x 4” pc of Velcro on the inside of the glass hatch and the mating surface of the plastic light housing - to hold the lamps in place until the rear gate was closed.
I ran the wire harness on the inside under the trim all the way up to the front and through the grommet in the firewall. The flat 4 wire was routed and secured up to the Adapter 4 pole to 6 pole that I had fastened to the Blue Ox base plate.
The actual installation of the SMI unit and assorted parts went rather smoothly. Most difficult issue was the lack of working space in front of the driver’s seat area. Installing the screw that holds the G force controller on the front (the side towards the front of the car) was difficult as it was almost a blind installation due to lack of room. The nut and fender washer used through the fire wall for attaching the air cylinder cable bracket was a challenge to reach - tight fit with not much room for one's hand and arm.
Other than that, no big surprises – just a lot of tedious steps to do when you want to be sure that it is being installed properly – take your time and don’t be in a hurry.
Once everything was installed – it all worked when I checked the system out. The only thing that may seem a bit odd is that when setting the G force initially, the compressor will shut off while adjusting per instructions. To do this initial adjustment, the wife stepped on the brake in the Motorhome, with the switch “On”. The compressor starts, and the brake is pushed down by the Air Cylinder, at which time I slowly adjusted the G force until the compressor shuts off. I secured the adjusting bolt and I told the wife to take her foot off the brake and then re-apply them. The compressor did not start again and the air cylinder did not apply the brakes in the Jeep. After setting the G force per instructions, the unit didn't turn on when the brakes in the Motorhome were applied - but since we were not moving - all I can assume is that the brake system will function while slowing down once the accelerometer setting (the sensitivity setting on the G force box) has been met. I assume that the sensitivity setting method includes a way to ensure the Jeep brakes are not engaged too frequently and only until needed.
This is the only step that is a tad bit confusing without an explanation as to what to expect once the G force sensitivity is set.
Lastly, I checked the brake away switch and it turned the compressor on and applied the brakes as expected.
Overall - the installation went rather smoothly. Can't wait to see how the product works once we hit the road. I'll check back and provide an update later.

Mike A.


Still working as expected, trouble free and no problems since the install.

Show More Reviews

See what our Experts say about this Demco Tow Bar Braking Systems

  • Troubleshooting A Non-Working Indicator Light For The Demco SBS Stay-IN-Play Braking System
    The LED indicator light for your Demco Stay-IN-Play DUO Supplemental Braking System w/ Wireless Coachlink Monitor # SM99251 only gets power when the brake light switch of the tow vehicle is activated. If you spliced into the incorrect wire or used quick splice connectors and aren't getting the best connection then it could just not be receiving the signal to light up. If you could tell me the year/make/model of the vehicle you're towing I'd be happy to look into the brake light switch wire...
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  • Does Demco Stay-IN-Play Duo Flat Tow Brake System Use Vehicle Brake Booster Vacuum to Operate
    Great question, Bob! The Demco Stay-IN-Play Duo Flat Tow Brake System # SM99251 actually activates the vacuum in your vehicle so the vehicle brakes work more naturally - it doesn't rely on the vehicle's vacuum system to operate. If your vehicle happens to not utilize vacuum braking then there are provisions for this on page 16 of the installation instructions.
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  • Will the SMI Stay-IN-Play DUO # SM99251 Fit a 2018 Jeep JL Wrangler
    The SMI Stay-IN-Play DUO # SM99251 is actually a universal supplemental braking system so it will be compatible with your 2018 Jeep JL Wrangler. If you check out the attached installation video of this system on a 2017 Jeep Wrangler you can see that the only time this system really connects to your vehicle is for the ground (to a bare metal surface) and your battery for power. At this time (February of 2018) we have not been able to test fit very many products on a 2018 Jeep JL Wrangler...
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  • Where is Fuse Located on Demco SBS Stay N Play DUO System
    The 15 amp fuse that you are looking for would be on the power wire that runs up to your Honda CR-V battery. It should be red in color and probably the closest thing to the battery. The kit would have came with a 20 amp fuse but if you lost it the style is ATO.
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  • Will Heat be Concern with Demco SBS Duo Mounted Near Brake Booster
    Since you would plan to mount the Demco SBS DUO on a bracket near the brake booster that would be far enough from heat sources to not be an issue. You just wouldn't want it right near exhaust components as they get the hottest.
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  • Supplemental Braking System Recommendation for a 2010 Jeep Wrangler
    Our installers here prefer to install the SMI Stay-IN-Play DUO # SM99251 on most vehicles, including Jeeps. It is one of the lower cost options but works very well and does not require additional accessories like most other systems. Once it is installed you will not have to worry about it again. I have included a link to a video showing an example installation on a similar Jeep.
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  • Recommended Fixed Supplemental Braking System for a 2017 GMC Terrain
    I recommend the Stay-IN-Play DUO, part # SM99251. It's a permanently installed braking system, like you're looking for, so all you need to do is flip a switch to activate it when you're ready to tow. Instead of using a cylinder and bracket that pushes your Terrain's brake pedal the DUO's actuating cylinder mounts to the brake pedal arm and connects to the firewall. The actuator doesn't get in the way and doesn't need to be removed or unhooked at all. Just flip the switch back off and...
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  • Supplemental Braking System Recommendation for 2018 Chevy Sonic
    The best supplemental braking system we have for your 2018 Chevy Sonic is the SMI DUO part # SM99251. This is a permanent install kit which means you install it once and you're set and don't have to reset up a system every time you want to flat tow. It's our installers favorite kit because of how much easier it is to install over the other similar kits and because of how well it works. I attached an install video for this kit on a similar 2014 Chevy Sonic as yours. I also attached a video...
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  • Does the Engine Need to Be On So Brakes Work Properly While Flat Towing 2010 Ford Explorer
    No, the vehicle motor will not need to be running while towing the vehicle in order for the brakes to work. When checking the owners manual for an Explorer, I found that if your 2010 Ford Explorer is a 4WD vehicle, Ford recommends that an accessory neutral tow kit be installed on the vehicle in order to flat tow. If a neutral tow kit is not installed, Ford has determined the vehicle should not be towed with all four wheels on the ground. This accessory kit is available through your local...
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  • Does Tow Mode of 2018 Jeep Grand Cherokee Affect Fuel Mileage When Towing
    Even if you could undue the shifting programming of your vehicle in tow mode you'd find that the fuel mileage is going to still be just as bad. The weight and wind resistance of your trailer is what is killing the mileage more than the way it shifts. Unless it's not letting you shift into overdrive on the highway the tow mode would not be affecting your mileage more than just towing.
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  • Instructions for Demco SBS DUO Supplemental Braking System
    I attached a link on this page for the Demco Stay N Play DUO part # SM99251 that you mentioned. They are not specific to your 2019 Ford Ranger but they will guide you through the install process. I also attached an install video link for this kit on a 2019 Ford Ranger that will show you exactly how we installed in on a 2019 Ford Ranger like yours.
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  • Permanent Install Supplemental Braking System Recommendation for Flat Towing 2005 Honda Element
    The SMI Duo part # SM99251 that you mentioned is going to be your best option. It works just as well as the Inivsi-Brake yet installs much easier. If the permanent install route is what you are wanting the DUO is hands-down the best option. Our installers here love it. If you are paying for an install somewhere it will also be much less expensive to go this route. The Invisi-Brake is also not listed as a fit for your Element either at this time.
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  • Are Breakaway Switches Universal
    All breakaway switches like the one included with the SMI Stay-IN-Play DUO Supplemental Braking System # SM99251 work the same way and they are essentially universal. You can certainly use your existing one and keep the one included in the SMI kit as a spare. You can refer to the linked articles for details on installing and testing your breakaway.
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  • Can 2013 Camry LE 6-Speed Auto Transmission Be Flat Towed
    According to Remco Towing, one of our key resources for flat towing information, the Toyota Camry from model years 2000 - 2012 can be flat towed but a lube pump kit LP-BK01-010 is recommended for the U241E transmission. The 2013 model year is not listed so the best thing to do is check your owner's manual under the heading "recreational towing" or "flat towing" to see what the folks at Toyota have to say. Naturally it is best to follow any guidelines from the vehicle manufacturer about...
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  • SBS DUO Braking System Replace Air Force One for Setup that No Longer Has Air Brakes on Motorhome
    You'd have to go with a new braking system altogether like the SBS Demco DUO part # SM99251 as there isn't a kit designed for replacing just the motorhome portion of your Air Force One and allows it to work with non-air brakes.
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  • Does SMI Supplemental Braking 2016 Ford Fiesta Know Difference Between Turn Signals & Brake Lights
    No as the SMI part # SM99251 is designed to recognize the difference between turn signals and stoplights when determining if the brakes or just the blinkers are being applied. I attached an install video for this braking system on a similar 2014 Ford Fiesta for you to check out as well.
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  • Will The Demco Stay-IN-Play Duo Flat Tow Brake System Work On Vehicles Without Power Brakes?
    While the Demco Stay-IN-Play Duo Flat Tow Brake System # SM99251 does have the ability to work with vacuum boosted brakes it will still work on other vehicles as well. This is covered in the installation instructions as you will simply install the vacuum line with the check valve open to vent. It can also be used on vehicles with hydraulic or electric boosted brakes.
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  • Does Demco SBS Stay-IN-Play DUO Work with Manual Transmission Vehicles
    Yes the Demco SBS Stay-IN-Play DUO Supplemental Braking System # SM99251 that you referenced does work with vehicles that have a manual transmission.
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  • Does Check Valve of SMI DUO Braking Kit Have to Be Used to Install in 2018 GMC Canyon
    You do have to install the check valve of the SMI DUO part # SM99251 to your 2018 GMC Canyon. What you sent in a picture of doesn't appear to be a check valve. It looks like it may be a tee valve or possibly a vacuum reduce so you would want to install the check valve of the DUO like the install instructions indicate as well as install video I attached that shows this installed on a similar Colorado as your Canyon.
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  • Whats Best Tow Bar Supplemental Braking System for 2018 Jeep JK Wrangler Unlimited
    The easiest to install and best performing permanent install style of supplemental braking is the DUO part # SM99251 by far. It's what I would recommend for you. We had chance to install this on a 2018 Wrangler like yours and we found there were no issues with the brake pedal either. Check out the attached install video for more info on this.
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  • Why Isn't The Demco SBS DUO Supplemental Braking System Activating When At A Stand Still
    The Demco SBS Stay-IN-Play DUO Supplemental Braking System - Proportional # SM99251 has an inertia sensor that detects deceleration and signals the system to activate the brake pedal with a proportionate amount of pressure. Because of this if you're sitting at a stand still and trying to test the system it will not activate. I recommend slowly rolling through your neighborhood to test the braking function of the system.
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  • How does the Demco Stay-In-Play's break-away switch attach to the vehicle?
    The Demco SBS Stay-IN-Play DUO Supplemental Braking System - Proportional # SM99251 comes with a bracket that is already attached to the break-away switch. It has a bolt hole in it to easily attach to the front of your 2021 Jeep Cherokee. (I attached a photo of this switch installed with a bolt/screw.) There is no other bracket to attach this to your vehicle's front end.
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  • Demco SBS Stay-IN-Play DUO - Notification Light Is Flickering After Alternate Wiring
    The notification light for the Demco SBS Stay-IN-Play DUO Supplemental Braking System # SM99251 should be solid when it is on and it should not be flickering. It is intended to be wired to the cold side of the brake switch. This is the wire that is cold and only has 12v when the brake pedal is pressed. It should be a white/brown wire on a 2011 Wrangler. Is it working as intended now that you turned the braking up? If so, I suppose there is no harm in the way you have it hooked up. I agree...
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  • Forgetting to Turn Stay-In-Play DUO Braking System Off Before Driving Vehicle
    I spoke with my contact at Demco and you can rest easy because he said accidentally leaving the switch on for the Stay-In-Play DUO Braking System # SM99251 while driving the vehicle isn't going to cause any actual harm to the system or the Jeep. Really the only potential issue is one you would have noticed anyway. If you happen to have the in-cab LED indicator wired to the brake light circuit it would have illuminated every time you applied the brakes while driving the Jeep. This probably...
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