bing tracking image
  1. Accessories and Parts
  2. Hopkins
  3. Tow Bar Wiring
  4. Extensions
  5. 4 Flat to 4 Flat
  6. Straight Cord
Hopkins 4-Pole Flat Wiring Extension - 120" Long

Hopkins 4-Pole Flat Wiring Extension - 120" Long

Item # HM48235
Our Price: $16.67
You Save: 30%
Accessories and Parts
Orders above $50 qualify for Free Shipping
Shipping Weight: 0.53 lbs
In Stock
zoom in icon
slider vertical icon
zoom out icon
Comment field cannot be left empty.
Name field cannot be left empty.

Thank you! Your comment has been submitted successfully. You should be able to view your question/comment here within a few days.

Error submitting comment. Please try again momentarily.

Product Images

Customer Photos


Need help with installation?
Locate installers near me
This 120" loop extends your current 4-way connector for more flexibility when towing. Ideal for connecting your towed vehicle to your RV. 1-636-306-4830 to order Hopkins accessories and parts part number HM48235 or order online at Free expert support on all Hopkins products. Great prices and Fastest Shipping for Hopkins 4-Pole Flat Wiring Extension - 120" Long. Accessories and Parts reviews from real customers.
  • All Info
  • Reviews (35)
  • Q & A (0)
  • Videos (1)
  • Photos
  • Why etrailer?

Hopkins Accessories and Parts - HM48235

  • Tow Bar Wiring
  • Extensions
  • 4 Flat to 4 Flat
  • Hopkins
  • Straight Cord

This 120" loop extends your current 4-way connector for more flexibility when towing. Ideal for connecting your towed vehicle to your RV.


  • Wiring harness extends your current 4-way connector for more flexibility when towing
    • Perfect for running power from your RV to your towed vehicle or trailer
  • Terminals resist corrosion
  • Dimensions: 120" long

48235 Hopkins 4-Way Flat Extension - 10' Long

Installation Details HM48235 Installation instructions

California residents: click here

Video of Hopkins 4-Pole Flat Wiring Extension - 120" Long

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

Video Transcript for Hopkins Tow Bar Wiring HM48235 Review

Today we're going to be taking a look at the Hopkins 4-Pole Flat Wiring Extension. This wiring harness is going to extend your current 4-way connector for more flexibility when towing. If you need some extra length with your wiring connectors for your 4-way flat, this is going to be a perfect solution for you. This is going to be ideal for running power from your RV to your towed vehicle or trailer. It's going to feature corrosion resistant terminals. These are going to last a long time, they're going to stand up well to the elements, and they're going to do a great job at resisting rust and corrosion, making sure to send through a nice, strong signal.

The unit's going to measure about 120 inches long, which is going to be about 10 feet long, so it's a pretty long wiring extension or harness. On this side right here, it's going to come with a dust cap to keep dirt and grime out of the connection points. That's going to do it for today's look at the Hopkins 4-Pole Flat Wiring Extension.

Customer Reviews

Hopkins 4-Pole Flat Wiring Extension - 120" Long - HM48235

Average Customer Rating:  4.9 out of 5 stars   (35 Customer Reviews)

This 120" loop extends your current 4-way connector for more flexibility when towing. Ideal for connecting your towed vehicle to your RV.


I used this product to "extend" tag lights to the rear of my camper. In conjunction with this, I also used a waterproof wiring box. I've had them on the camper for a year now, and have towed my little aluminum boat behind the camper on several occasions, it works like a charm! As an aside, I wired in a remote camera into the tail-lights wiring on this harness, now I turn on my driving lights and my remote camera allows me to monitor the boat in 'real-time' while I'm towing. Overall, this works like a charm. Thanks, E-trailer!

A year later my original view still stands. This product is still working excellent for my needs.
Mike - 08/28/2022


I’m using this to test my trailer without having to move my trailer from its storage on the sude of my house. It works great!


Although I am commenting on this product, I actually would like to comment on the following products. I purchased a brake system, tow bar, base plates and wire harness from etrailer. All of my orders were filled in a timely manner. When I reached out for technical assistance, the advisors were readily accessible. All of the products were installed by me. All of the products were very easy to install by using the video and instructions.


Delivered as advertised. I use with my F350 and tow extension when traveling with my truck camper and towing a boat.


This extension works well for me. I used it to extend the pigtail on my camper to the back so I could tow my aluminum boat behind the trailer. Has been working excellent for a year, shows no weathering/cracking. Mike


So, I have a slide in camper on my F350, and to haul a boat trailer I needed a loooong extension for the trailer wiring hookup. I have a Super Hitch with a three foot extension that just barely pokes out from the bottom of my camper and the wiring extension from etrailer works just like a wiring extension is supposed to work. It makes my trailer lights light up as needed.
Oh, the Super Hitch and the super dooper heavy duty three foot extension came from etrailer as well ( they didn't let me know I'd need a wiring extension but I am guessing that they were guessing that I was not stupid) and are very well made. No problems at all hauling my beautiful, but kind of wide in the ass sailboat while the slide in camper is in the bed of the truck. I know this doesn't have much to do with a trailer wiring extension but really, what can you say about four (it's four right?) wires and a couple of connectors? It works as it should. The price was right. The delivery was exceptional. They might be faster than [other sites]. etrailer is (are?) my go to folks.


This wiring harness was exactly what I needed to complete the relocation of my rear license plate on my motor home.

No issues and is still working after 1 year.
Paul L - 03/21/2020


Great product!! Works wonderfully!


I gave it a 4 star because I haven’t used it on the road. But it appears to be a quality made product.


The website is excellent. It made my search for the product I needed very easy. Deliv;ery service to my front door was surprisingly prompt. seems to offer everything related to trailers, rvs, etc. Prices are good. Service is excellent.

Thanks once again.


Product is of superior quality, as is the service. In addition, tons of installation information is available on the website. All in all, a wonderful experience.

Thanks for the review on the Hopkins Wiring Extension, Pierre!!! Hopkins appreciates your business and is glad that we could help make this a wonderful experience for you.
Hopkins C from - 05/17/2017


This "male to female" extension cable fit the connector at the TOAD end fine. It however did not fit the connector on the RV due to the rubber ring around the connectors. I was able to cut the ring off that end and it fit the RV connector fine then.


Very good packing and quick shipping. All the items are good quality. It was and easy job. Good support from the video's which were well done and the free shipping helped make my choice to purchase from e trailer.


Delivered quickly and worked as advertised. I am very happy with this product and will shop/order from etrailer again.


Just as described- the extension fit perfectly and worked.

Thanks for the review on the Hopkins Wiring Extension, Ryan!! Hopkins appreciates your business.
Hopkins C from - 06/23/2017


Just what I needed to extend the wires between my toad and motorhome.


Very informational when orders my products, videos were very helpful. They were very prompt on getting my order out and delivered to me, thank you very much.


Just as described and pictured. Item arrived quickly and was packaged very well. Works great. Hard to find item.

Thanks Matt for reviewing the Wiring Extension!! Hopkins appreciates your business.
Hopkins C from - 05/31/2017


I was looking for a 6 ft. extension and found this. It works fine.


Haven’t used this extension yet but looks well made. Glad to have it. Thanks again


Perfect for my need. Good quality and durable. Works great.


Exactly what I needed.

Thanks Scott for another great review and rating!! Hopkins appreciates your business.
Hopkins C from - 07/10/2017


Just what the Dr ordered Nice




Was what I expected, good product.

Show More Reviews

See what our Experts say about this Hopkins Accessories and Parts

  • Can 4-Way of Tow Vehicle Bypass Fifth Wheel Trailer and Connect to Boat Trailer
    The 7-way and 4-way of your 2014 Ford F-150 will both be active so you can use an extension like the part # HM48235 (you might need a few) to go from the 4-way on the truck to the 4-way on the boat trailer. This extension is 120 inches long.
    view full answer...
  • Tow Bar Wiring Harness Recommendation For 2012 Ford F-150 With EcoBoost
    We do have the wiring kit you need for your 2012 Ford F-150. I recommend the Hopkins Custom Tail Light Wiring Kit, part # HM56000. This plugs into your F-150 wiring behind the tail lights and plugs into the RV. This will not affect the electrical system of your F-150 when not flat-towing. I also recommend an extension like part # HM48235. This extension is used to connect the F-150 to the RV. There are 5 items needed when you are flat-towing. You need base plates, a tow bar, safety...
    view full answer...
  • 4-Pole Wiring Extension for Tow Ready Tow Light Kit 73864
    If you want to add 10-feet of additional 4-pole wiring to the Tow Ready Magnetic Tow Lights # 73864 you can simply use a 4-pole extension cable. This will avoid the need to cut and splice the lights' wiring harness. Hopkins offer 10-foot extension # HM48235 that will plug right in. I suggest you apply some dielectric grease like # 11755 to the connection point and secure the two mating connectors with a zip tie.
    view full answer...
  • Gauge Wire Used for the Hopkins 4-Way # HM48235
    The Hopkins part # HM48235 has 16 gauge for wires. For a 4-way that has all 16 gauge wire you would want the Wesbar 4-Pole Flat Connector # W787264.
    view full answer...
  • Solution for Towing Trailer with 4-way Behind Trailer with 7-Way
    You could use the Curt 7-way to 4-way adapter part # C55384 to add in a 4-way basically behind your current 7-way and then use an extension like the part # HM48235 which is 12 feet long. You could use multiple extension if your camper is longer as needed.
    view full answer...
  • Recommended 4-Flat Wiring Harness for a 2003 Chevy Tahoe
    The Hopkins Custom Tail Light Wiring Kit item # HM56101 will fit a 2003 Chevy Tahoe. However, it is for when your Tahoe is being flat towed to control your tail lights by the RV. It will not allow your Tahoe to control trailer lights. To add a 4-way connector that can be used to control trailer lights you will need the Curt T-Connector Vehicle Wiring Harness for Factory Tow Package item # C55384. This harness will allow you to keep your Tahoe's 7-way connector as well. I have linked...
    view full answer...
  • Wiring Dome Light and 3rd Brake Light on Camper Shell With Ability to Easily Disconnect Wiring
    In order to wire this up the way you want, and also be able to disconnect it easily, I suggest using the Hopkins 4-Pole Flat Wiring Extension - 120" Long # HM48235 and the 3rd Brake Light Logic Module # PP20-702. I would start by cutting the Hopkins wiring extension in the middle (you can measure first and cut according to how much length you need for each end). The two different 4-way plug ends will be how you connect and disconnect the camper shell wiring from the vehicle. The idea...
    view full answer...
  • Can I Use A Light-Up Rectangular Trailer Hitch Receiver Cover With My Thule T2 Classic 4 Bike Rack
    I can definitely help you get an extension for the Light-Up Rectangular Trailer Hitch Receiver Cover - Brake, Tail, Turn - 2" Hitches, part # CR-007XL. I did some investigating and your Thule T2 Classic For 4 Bikes is 55" from the center of the hitch pin to the furthest edge of the bike rack. I do have an extension that will work, but it is 120" long. The Hopkins 4-Pole Flat Wiring Extension - 120" Long, part # HM48235, will definitely work, but you will have to zip tie the excess wiring....
    view full answer...
  • Installing A 4-Pole Trailer Connector To 5th Wheel Trailer
    The Curt RV Bumper Hitch, # C19101 is for RV bumper use only and fits 2" x 4" RV bumpers. This will require a customized wiring job as you will probably need to remove interior trim panels to access the taillight wiring of your 5th wheel to evaluate what is the best route. You can also make contact with the OEM and request guidance for best route. Once you find a way into the wiring, simply splice in the 4-Pole 60" Long Vehicle End (Includes 4 wire taps) Item # 18002. I do recommend...
    view full answer...
  • Length of Wiring on Pilot Brake and Tail Light Trailer Hitch Receiver Cover # CR-007A
    I checked with my contact at Pilot Automotive for the length of the wiring included on their Brake and Tail Light Trailer Hitch Receiver Cover # CR-007A. My contact advised that the length of the wiring itself is approximately 14-inches. If this is not long enough for your installation we offer 4-pole extensions such as 12-inch # HM48145 or 120-inch # HM48235, both from Hopkins.
    view full answer...
  • Longer 4-Way Harness Recommendation to Go Along with TLL9RK Kit
    The part # TLL9RK comes with a 25 foot long section of 4-way wiring. For an additional length of 10 feet of this wire with the correct connections you would want the part # HM48235. This will give you 35 feet of wire. For additional length you would want the part # HM47115 which will give you additional 4 feet.
    view full answer...
  • Availability of 8 Foot Long 4-Way Wiring Extension
    We do have 4-Way flat to 4-Way flat extension adapters available, however they do not feature a coiled wire like you mentioned in your question. I recommend taking a look at the Hopkins 4-Pole Flat Wiring Extension # HM48235. This extension measures 120 inches (10 feet) long, which is a bit longer than you need but is the closest option available. We also have a 6 foot extension loop with part # RM-300150-00. I have attached a couple short video demonstrations on these products that...
    view full answer...
  • 4-Way Prong Wiring Needed That is 8' Long
    If you are looking for just an extension then the Hopkins 4-Pole Flat Wiring Extension # HM48235 that you referenced is 10' long and will be exactly what you are needing. For a flat towing application we have the common 4-Way round connectors like part # HM47046 which is 8' long or for a 4-Way flat connector you would need both the part # RM-300150-00 (6') and the part # HM47004 (2'). Let me know if you are looking for something different and I can make a recommendation for you.
    view full answer...
  • 4-Pole Wiring Extension for Connecting Reese RAM Lighted Hitch Cover RP86531 on 2015 Ram
    If you want to install the Reese RAM Lighted hitch cover # RP86531 and its 16-inch-long 4-pole wiring harness is not quite long enough to reach your truck wiring you can simply use an extension. We have 4-pole extensions in many lengths, such as the 12-inch # HM48148, 24-inch # HM47004 and 48-inch # HM47114. We also have a 10-foot extension # HM48235 but this one does not have the special Hopkins Easy-Pull connectors found on the other extensions listed.
    view full answer...
  • Available Lengths of 4-Pole Trailer Wiring Extensions
    We do offer 4-pole extensions that can be used with the Tow Ready 7-Way to 5-Way/4-Way Trailer Adapter for Vehicles with Lamp-Out Sensors Towing Trailers with LEDs # TR20141. We have 4-pole extensions in many lengths including the 10-foot # HM48235, 4-foot # HM47115 and # HM47114, and 2-foot # HM47004.
    view full answer...
  • 4-Way Trailer Wiring Extension Recommendation to Allow Flat Towed Vehicle & Trailer Behind Vehicle
    What you'll need is a long 4-way extension spliced into the 4-way you have at the back of the RV. For that you'd want to use the part # HM48235 which is 120 inches long. You'd need to cut off the one end and then use quick splice connectors like # SWC501746-1 to connect to the RV wiring. This will allow the 4-way to operate the CR-V taillights and then you'd be able to route the jumper wire to the back of the CR-V where you can then plug it into your trailer.
    view full answer...
  • Can InvisiBrake be Wired to a Magnetic Light Kit Instead of the Vehicle Wiring in a 2012 Honda CR-V
    There's no reason you can't wire the InvisiBrake Supplemental Braking System, part # RM-8700, to a magnetic light kit, like the Roadmaster # TL21RK. However, this will mean the magnetic kit is then attached to the InvisiBrake which is a permanent install. So the magnetic lights will be permanently connected to the CR-V as well unless you cut the wiring each time or find a different way to disconnect them. To do the install you just splice into the 4-wires on the magnetic kit instead...
    view full answer...
  • Recommended Parts for Flat Towing a 2013 Lincoln MKX
    The first thing that we will want to look at for your 2013 Lincoln MKX is a base plate kit so that we can attach the tow bar to your Lincoln. I recommend using the Blue Ox Base Plate Kit # BX2625 because it is very easy to use, and when you are not towing your MKX you can remove the base plate tabs for a better look when driving it around. The tow bar that I recommend for your setup is the Blue Ox Alpha # BX7380. This tow bar has a weight capacity of 6,500 lbs and includes the safety cables...
    view full answer...
  • Can 2010 Ford F-150 Automatic be Flat Towed
    I took a look at the online version of the owner's manual for your 2010 Ford F-150 and it looks like if you have the automatic transmission it is not recommended to flat tow the truck with all 4 wheels on the ground. Doing this may cause damage to the transmission so your safest route is to use a car hauler to pull the truck with all the wheels off the road. If you wish to proceed with flat towing though you would need to install a lube pump kit, which we do not currently offer. I do...
    view full answer...
  • Recommended Flat Towing Parts For 2013 Jeep Wrangler With ARB Stubby Bumper
    I reached out to my contact at Blue Ox and the baseplate that will work for your ARB Stubby bumper is the Blue Ox Base Plate Kit - Removable Arms, # BX1134. This gives you a 24 inch distance between bracket and fits Blue Ox Acclaim, Adventurer, Aladdin, Allure, Alpha, Ambassador, Avail, Aventa, and Trion tow bars. If you don't already have tow bars, I recommend the Blue Ox Alpha Tow Bar - Motor Home Mount - 6,500 lbs, # BX7380. This tow bar comes with the safety cables. To wire...
    view full answer...
  • Recommended Flat Towing System for 2010 Buick Enclave For Easy Install
    For your 2010 Buick Enclave and your Blue Ox Alpha Towbar # BX7380, I recommend the Blue Ox Base Plate Kit - Removable Arms # BX1708. This is a custom fit that will work perfectly with your system. The tow bar comes with the safety cables needed, so then you will simply need a high-low adapter bar compatible with your system. I have attached an article to assist as well as linked the page to your options. Then I recommend the Hopkins Custom Tail Light Wiring Kit for Towed Vehicles #...
    view full answer...
  • Adapter to Flat Tow a 2016 Jeep Wrangler Unlimited with EZ4 Base Plates Using a Blue Ox Tow Bar
    The adapter # RM-032 is a match for the EZ4 base plate kit that fits your 2016 Jeep Wrangler Unlimited, part # RM-521448-4. There is no adjsutment to be made. If you need other parts to setup the Jeep to be towed I recommend using the Hopkins wiring kit, part # HM56200, for lighting. It plugs in behind the Jeep's tail lights and provides a 4-way at the front to connect to the RV. You also need a Brake-Lite relay, part # RM-88400, to keep the Wrangler's lights from overriding the RV's....
    view full answer...
  • Solution for Adding Lights to Thule T2 Bike Rack Both in 2-Bike and 4-Bike Configuration
    The LED Light Kit # 98174LED and Bracket # BK70BB that you referenced seeing will work great for your Thule T2 Classic Bike Rack. It includes an 88" long offset y-harness (46" length for the driver side portion) that will be long enough to reach the Pilot's 4-Way when using the T2 in its 2-bike configuration and you could add a simple extension loop when you are extending out the rack in its 4-bike configuration. We have these loops available in various lengths, such as the...
    view full answer...
  • How to Flat Tow 2005 Jeep Liberty 4WD
    I took a look at the online version of the owner's manual for your 2005 Jeep Liberty and for the 4WD model it lists the following procedure for shifting the transfer case to N (Neutral) so that it can be flat towed with all 4 wheels on the ground: 1. Depress brake pedal, 2. Shift transmission into N (Neutral). 3. Shift transfer case lever into N (Neutral). 4. Start engine. 5. Shift automatic transmission into D (Drive) or manual transmission into any forward gear. 6. Release brake...
    view full answer...

< Previous

Do you have a question about this Accessories and Part?

  • Why

    At we guarantee:
  • Real product know-how.

    We make sure that the products we sell are what we say they are, and that they work the way they are supposed to work. Get real advice from a real person who has the knowledge and expertise needed to solve your problem.
  • Most detailed, accurate accessories and part information available.

    Because we take providing accurate product information seriously, we take our own detailed product photos, demo videos and installation videos, as well as verify measurements, instructions, and vehicle fit information.
  • Installations, made easy.

    We love helping people and have the most highly-trained customer service, hands-on experience, step by step videos and installation instructions.
  • Fast shipping.

    Your order is automatically routed to get out of our warehouse and to your door as quickly as possible. Receive free shipping on orders over $99.
  • Personalized service for life.

    We provide one-on-one, personalized service from the ordering process through the life of your product.
  • Trusted since 1946.

    We've been serving customers since our parts store first opened in 1946 and continue to be recognized by our customers, our vendors and third parties for exceptional service.
  • Returns Policy

    Need to return an item? No problem. Please read our Returns Policy for more information.

Info for this part was:

Employee Jameson C
Expert Research:
Jameson C
Employee Laura H
Written by:
Laura H
Employee Cole B
Installed by:
Cole B
Employee Alexander C
Updated by:
Alexander C

At we provide the best information available about the products we sell. We take the quality of our information seriously so that you can get the right part the first time. Let us know if anything is missing or if you have any questions.