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RoadMaster 4-Wire Connector - Vehicle End

RoadMaster 4-Wire Connector - Vehicle End

Item # RM-910030-1
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Create your own cord or replace the damaged ends on your RoadMaster 4-wire straight and Flexo-Coil electrical cords with this 4-pole, male connector. Lowest Prices for the best trailer wiring from Roadmaster. RoadMaster 4-Wire Connector - Vehicle End part number RM-910030-1 can be ordered online at or call 1-800-940-8924 for expert service.
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  • Reviews (33)
  • Q & A (0)
  • Videos (3)
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Roadmaster Trailer Wiring - RM-910030-1

  • Trailer Connectors
  • Vehicle End Connector
  • 4 Round
  • Plug Only
  • Roadmaster

Create your own cord or replace the damaged ends on your RoadMaster 4-wire straight and Flexo-Coil electrical cords with this 4-pole, male connector.


  • Replaces lost or damaged 4-pole, round, male connectors (vehicle end)

910030-1 RoadMaster 4-Way Round, Vehicle-End Connector

Video of RoadMaster 4-Wire Connector - Vehicle End

Videos are provided as a guide only. Refer to manufacturer installation instructions and specs for complete information.

Video Transcript for Roadmaster Wiring - Trailer Connectors - RM-910030-1 Review

Today, we're going to take a look at the Roadmaster 4-wire vehicle end trailer connector. Now, this connector will install in the vehicle that's being towed to allow you to plug in a 4-pin plug from the tow vehicle. This replacement socket will fit the Roadmaster 4-wire straight and the Flexo-Coil electric cords. Includes this nice spring-loaded cap that will automatically drop down to cover the connector when it's not in use. And to install your wire to this, you just run your wire back through here, make your connections to the 4-pin, and you're ready to go. Just to show you where those connections are made, to do it, you just take out this little Phillips head screw and once that screw comes out then just open the cover or the plate and then just tap it and you'll see the center comes out and there's your 4-pin. And on the very back is where you'll make your wire connections.

So, just run your wire through here, bring it out, make your connections, and then all you have to do is slide this right back in. Make sure the hole at the top lines up correctly. Once you get that hole to line up, then go ahead and take your . Let's get the little Phillips head screw. Once we get that put on the screwdriver ...

There we go . And just line it up with the hole and go ahead and tighten it back down. Then once you get it all tightened down it's secure and ready to go. Then you're all ready to plug in your connector. That should do it for the review on the Roadmaster 4-wire vehicle end trailer connector.

Customer Reviews

RoadMaster 4-Wire Connector - Vehicle End - RM-910030-1

Average Customer Rating:  4.9 out of 5 stars   (33 Customer Reviews)

Create your own cord or replace the damaged ends on your RoadMaster 4-wire straight and Flexo-Coil electrical cords with this 4-pole, male connector.


These 4 wire round connectors look quite robust and are priced right! Shipment was super quick. etrailer is the best!

Still working great after a year of use.
NormB - 02/28/2022


We just finished a makeover of our 1995 boat trailer. New bunks, sanded and painted but the best part of the project was the new LED lights from your company. They are so much brighter than the old incandescent bulbs that you really do feel safer driving down the road. We pulled the 20 year old wire out and replaced with new and used the 3M scotch loks to tie in. We were not sure the new style grommets would fit the old holes in the frame but they fit great. Your customer service was great, alerting me to a backordered reflector but recommended a replacement that worked fine. Patrick set up a Q&A page for me since I had questions about the best way to protect connections with dielectric grease, heat shrink and tape. Your website is one of the best with ease of navigation, complete pictures, great selection and thorough info, dimensions, etc. You guys really have your act together and also offer great value. I would not hesitate to purchase again and will recommend you when I can. I have attached a couple of pictures. Thanks for all your help. Wayne N.


Very helpful.good quality parts.very timely shipping.. would definitely use again..


Great product


Etrailer is a very solid company for all of my RV and trailer needs. They help me find the right product for my vehicles and have very helpful installation instructions and videos. Their pricing is reasonable and the shipping times are very good with excellent follow-up.


This 4 wire connector works as it should. Good finish and have used them in the past for many years with no problems. Good product and good service from trailer. The connector arrived on time.


The lighting kit connectors I purchased came on time and were packaged securely. Entire order and delivery process was flawless!


Works great with Road master tow bar.


The exact part I needed to connect the electrical on my towed vehicle. I had the part in two days. Excellent!


E.trailer had the product I needed. Delivered it promptly. Very Happy,


Used with bracket to mount connector to my 2012 Jeep.


Your price were better than any of your competitors and even my local parts houses. I have always been very satisfied with you products and prices and the quick shipping.


Quality item delivered as promised.


Received the product I ordered and I received it on time. I recommend this company. He made up earlier with those guys in them part of the show


Easy install. Working great after 7 months of constant RVing!


Used it for a test cable, worked great


Fits and works great on my tow car.


Good product


Was exactly what I wanted. Part worked great and the service was fast.


Timely delivered. As advertised.


Delivered on time


Just what the doctor ordered


Great service and follow up.
Tks r>Dave


fast delivery, great part.


Nice works well

Show More Reviews

See what our Experts say about this Roadmaster Trailer Wiring

  • 4-Pole Round Pin Trailer & Vehicle Connectors to Allow Conversion from 4-Pole Flat Connectors
    We offer trailer connectors, sockets and plugs in many connector formats that you can view in the linked article on trailer wiring. I also linked our main page for all 4-pin round connectors such as vehicle-side female socket # RM-910030-1 and trailer-side male plug # PK11402. We also have a kit with both, part # RM-910030-4 from Roadmaster. You'll want to be sure to wire the new connectors based on each wire's function, not by its wiring insulation color as this is not always consistent.
    view full answer...
  • 4-Way Flat Adapter Recommendation to Use with RoadMaster 4-Wire Connector # RM-910030-1
    Yes, the 4-way round to flat adapter part # ADP001 that you referenced will work with the RoadMaster 4-Wire Connector # RM-910030-1. It will plug right in and give you a 4-way flat to use.
    view full answer...
  • What is the Center Bracket for In Roadmaster Base Plate Kit # 1425-1, 2004 Jeep Grand Cherokee
    You are correct. The center bracket with the round hole in Roadmaster XL Base Plate Kit, # 1425-1, is for the wiring harness to mount to. A connector like # RM-910030-1 can be mounted in that bracket, or Pollack connector, # PK11404.
    view full answer...
  • Is a 7-Round to 4-Round Adapter for Trailer Lights Available?
    I can offer you a solution, though a 7-round to 4-round adapter is not available. What you will need to do is create your own by wiring a 7-round trailer end connector, # PK11700, and 4-round vehicle end connector, # RM-910030-1. I recommend going with the 14 gauge, Deka Jacketed 4-Wire, # DW04923-1, which is available per foot so you can get the amount you need. If you have an RV-style connector (which is often referred to as a 7-round), then the part you would be looking for is the Hopkins...
    view full answer...
  • Best Tow Bar and Flat Towing Components for 2016 Jeep Wrangler
    Since you said you want the best and lightest weight tow bar for your flat towing setup the Roadmaster Nighthawk part # RM-676 is the way to go. It's about 20 lbs lighter than the competition, is very easy to use, and comes with safety cables and and an umbilical wire kit. The correct base plate kit you'll want that fits your 2016 Jeep Wrangler and this tow bar is the Direct Connect kit part # 1444-3. Since we don't have any plug and play tow bar lighting kits the best option is the...
    view full answer...
  • 4-way Round Trailer Connector to 4-way Flat Connector
    I have a solution for you. However, we do not have an adapter to fit your 4-pin round connector on your trailer. Because of the rarity a 4-way round connector, I recommend either cutting off the 4-way round and attaching a 4-way flat, or splicing a 4-way flat into your wiring in addition to the 4-way round. To attach a 4-way flat, you can use part # HM48035. If you remove your 4-way Round connector, you will want to use butt connectors # DW05744-5. If you want to add the 4-way Flat...
    view full answer...
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  • Solution for 4-Way Adapter With 4-Way Flat Male End and 4-Way Round Male End
    Your typical 4-way flat to round adapter like the # ADP001 is the opposite of what you need on both ends. Although nobody makes an adapter like this, you can easily make your own. For the 4-way flat trailer end connection you can use the Hopkins Wiring Harness with 4-Pole Flat Trailer Connector - Trailer End - 4' Long # HM38138. You can cut the wiring harness down if you want it to be shorter but this gives you a decent amount of wire to work with. Then you will need the RoadMaster 4-Wire...
    view full answer...
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