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Hopkins Engager Trailer Breakaway Kit w/ Charger, LED Tester, Hardware, and 5 Ah Battery - Top Load
Hopkins

Hopkins Engager Trailer Breakaway Kit w/ Charger, LED Tester, Hardware, and 5 Ah Battery - Top Load

Part Number: 20400
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$64.11
Trailer Breakaway Kit
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20400 - Top Load Hopkins Trailer Breakaway Kit
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The built-in charger in this kit keeps the battery charged and ready to bring your single-axle or tandem axle trailer to a complete stop should it become disconnected from your vehicle. LED tester lets you easily check the battery's charge. Great Prices for the best trailer breakaway kit from Hopkins. Hopkins Engager Trailer Breakaway Kit w/ Charger, LED Tester, Hardware, and 5 Ah Battery - Top Load part number 20400 can be ordered online at etrailer.com or call 1-800-940-8924 for expert service.
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Hopkins Trailer Breakaway Kit - 20400

  • Kit with Charger
  • Single-axle
  • Tandem-axle
  • Top Load
  • Hopkins
  • LED Tester

The built-in charger in this kit keeps the battery charged and ready to bring your single-axle or tandem axle trailer to a complete stop should it become disconnected from your vehicle. LED tester lets you easily check the battery's charge.


Features:

  • Makes sure your trailer safely stops if it ever separates from your vehicle
    • When the pin gets pulled from the switch, a signal is shot back to your trailer brakes to activate
  • Automatically charges battery with the built-in charger when connected to your vehicle
    • Won't overcharge the battery
  • Lets you test battery status with the push of a button
  • Mounts on the inside of your trailer's A-frame
    • Top-loading case provides easy access to battery from above
    • Self-tapping screws are sold separately
  • Breakaway switch installs with self-tapping screws
  • Protects battery from rain and debris with durable, plastic case
  • Includes breakaway switch, charger, battery, battery box, and wiring


Specs:

  • Application: single- and tandem-axle trailers with electric brakes
  • Battery:
    • Voltage: 12V
    • Type: lead acid
    • Capacity: 5 amp-hours
  • Charger:
    • Lead wire length: 43-1/2"
  • Breakaway cable length: 48"
  • Breakaway switch:
    • Dimensions: 7-1/2" long x 3-1/2" wide x 6-1/2" tall
    • Lead wire length: 16-1/2"
  • Battery box:
    • Dimensions: 4" long x 8" wide x 6-1/4" tall
    • Mounting hole spacing:
      • From center to center vertically: 3"
      • From center to center horizontally: 7-1/4"
  • 90-Day warranty


Note: A breakaway system is required by law in most states for trailers that are equipped with electric brakes and have a GTW of at least 3,000 lbs.


Built-In Battery Charger and Tester

The integrated charger keeps the included battery charged and ready to go. At any time, if you would like to see what the state of the rechargeable battery is, just push the green button and LEDs will light up to indicate the battery's status. If it's green, it means the battery is fully charged. Yellow shows it's currently charging, and red indicates a low battery.


Image of LED indicator showing the status of your battery

Quick Tips:

  • When you store your trailer, be sure to keep the pin plugged into the breakaway switch. If the pin's removed for an extended period of time, dirt and moisture can get into the switch and cause corrosion that could keep it from activating when you need it.
  • A breakaway system needs to be able to apply the trailer brakes fully for at least 15 minutes. In general, the heavier your trailer, the higher amperage battery you'll need for the breakaway.


20400 Hopkins Engager Push-To-Test Trailer Break Away Kit with Built-In Charger - Top Load - 5 amp/hrs

Installation Details 20400 Installation instructions


California residents: click here


Customer Satisfaction Score:


Customer Reviews

Hopkins Engager Trailer Breakaway Kit w/ Charger, LED Tester, Hardware, and 5 Ah Battery - Top Load - 20400

Average Customer Rating:  4.8 out of 5 stars   (694 Customer Reviews)

The built-in charger in this kit keeps the battery charged and ready to bring your single-axle or tandem axle trailer to a complete stop should it become disconnected from your vehicle. LED tester lets you easily check the battery's charge.

by:

Item received damaged. The molded pieces inside the box holding the battery in place were broken. I was surprised how thin and fragile they were; at least 1/3 the thickness of the original non-electric Hopkins box I was replacing. etrailer quickly sent an RMA.



by:

This is a good product. I did add some foam padding inside this battery box to keep the battery from moving around inside the box. I travel all over the lower 48 and sometmes not on very good roads. Etrailer has always provided me with quality products and exceptional service.



by:

The customer service is top notch! The items I ordered were not currently in stock, but the team over at etrailer kept me informed as to when it would be in stock and even gave me a different option if I wanted it. I chose to wait it out. The break away kit with charger seems well built and was quite easy to install I also ordered the trailer wiring- 7 pin kit with junction box also easy to install and it organized all the wire connections beautifully.



by:

Works well, but the graphic overlay on top is not long-term weather-proof. I had to order a replacement because the overlay was completely destroyed after about 3 years parked outside. Park under cover, or install this box where it is shielded from the elements.



by:

I lost the lid on my original Hopkins unit. So I merely removed the lid from the new unit, snapped it on to the old body, connected the wiring and installed the new battery. Luckily I had the fast type electrical connectors. The change out took about 20 minutes.



by:

Following the installation instructions made the work fairly straightforward. The hole pattern for the case was as-advertised, so it fit perfectly where the old kit was installed on the trailer rail.

Dan

4/8/2023

Cant tell you. I sold the trailer with the boat!



by:

This battery kit is a perfect replacement for the battery that was on my 16 ft trailer to operate the brakes, in case of trailer breakaway. The charging light comes on when connected to my Tacoma pickup truck, which keeps the battery charged. This is a great product, and I'm very pleased with it.



by:

Would definitely purchase again! This is a good kit for setting up a break-away on your trailer. Make sure to mount it out of the way so that it doesn’t get impacted by any thing.



by:

Why the hell don’t the 7 way cables have standard color coding ?



by:

The breakaway control is a replacement for the one on my tilt trailer works great



by:

It arrived a day early, and it was exactly what I ordered! Go figure. Now I can put this in my ancient horse trailer instead of stacking rocks in the yard.



by:

I bought these brake batteries when rewiring two old horse trailers. This is the third & fourth trailer I've rewired, so I'm pretty used to it by now. Everything about this product went together easily. Routing the wires on the trailer was another story, as usual.

I sold one trailer, but I've been using the other trailer infrequently for about a year now, and the brakes seem to be working quite well. I haven't had an occasion to test the breakaway battery out on the road, fortunately, but the little lights on the top indicate that it's maintaining a good charge, and the breakaway switch did lock up the brakes when I tested it in my shop.

BTW, I *love* pairing these with the Bargman coiled wiring plugs. They're so much nicer to use than straight wires.



by:

Perfect replacement. Fast delivery with a good price.



by:

I am generally happy with Hopkins quality products. This one is one that I am very happy with. Quality is superbe.



by:

Very good product. Clear instructions made installation easy. Solved my wiring problem.



by:

I really wanted a 9 ah setup to insure ample power but I could not find one that also had a push button test feature so I decided I would just mount two and configure them to work together. It uses two, dpdt switches to switch the units on and off line either independently or together. This gives me assurance of ample power and a backup to each other..
One thing I'm going to do is run a diode isolated circuit to the cold side of the breakaway switch to the l.e.d. Break lights so if the trailer ever did come lose, it will also apply the break lights. The two diodes will keep the tow vehicles breaklight power from back feeding into the actuator's emergency stop circuit.



by:

Just what I needed



by:

Product works well
Applies power to
the electrical brakes if the cord is pulled
Easy to put the cord back into the switch
Used on a homemade trailer
That was made to carry bale barns
(hay feeder for horses)



by:

Very easy to install and I feel it is made to last. I am very pleased with my purchase as well as the customer service provided by E trailer.



by:

Simple installation , wiring diagram on the top cover. Easy Peasy!!



by:

all worked well



by:

Thankfully I haven’t had to have an operational use of this. It was a straightforward installation and is easy to check the battery status. I would order this again, if needed.



by:

This unit replaced the crusty 30 year old battery on my car trailer.
Easy installation if you do what I usually don’t. That is, read the instructions!!
The status LED charge indicator is a great feature.



by:

Opened battery box and tabs that hold battery in place are broken

Etrailer Expert

Jenny N.

9/26/2023

Oh no! I will have our Customer Service team contact you.



by:

exactly as described and super quick sh ipping


25
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