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  1. Flat Tow Wiring Harness
  2. Optronics
  3. Removable Tail Light Kit
  4. Bypasses Vehicle Wiring
  5. 4 Flat
  6. Universal Fit
THIS ITEM IS NOT A FIT FOR
2005 Audi S4
etrailer Installation
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Optronics

Universal Magnetic Tow Lights - 20' Wiring Harness with 4-Way Flat Trailer Connector

Part Number: TL21RK
In Stock
$61.88
Retail:$79.20
You Save: 22%
Flat Tow Wiring Harness
Not Confirmed to Fit

2005 Audi S4

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etrailer Installation
We'll connect you with nearby partnered installers who know this exact setup.
Stick these heavy-duty magnetic lights on the back of your car and they'll stay there. Nice and secure, these are also the easiest way to get brake and turn signals on your towed car, trailer, or cargo carrier without doing any hardwiring. 1-800-940-8924 to order Optronics flat tow wiring harness part number TL21RK or order online at etrailer.com. Free expert support on all Optronics products. Great prices and Fastest Shipping for Universal Magnetic Tow Lights - 20' Wiring Harness with 4-Way Flat Trailer Connector. Flat Tow Wiring Harness reviews from real customers.
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  • Reviews (210)
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Optronics Flat Tow Wiring Harness - TL21RK

  • Removable Tail Light Kit
  • Bypasses Vehicle Wiring
  • 4 Flat
  • Optronics
  • Universal Fit

Stick these heavy-duty magnetic lights on the back of your car and they'll stay there. Nice and secure, these are also the easiest way to get brake and turn signals on your towed car, trailer, or cargo carrier without doing any hardwiring.


Features:

  • Gets turn and brake signals on your towed car without having to tap into its wiring
    • Eliminates risk of electrical damage to towed car
    • Makes your tow setup safe and legal without a permanent installation
  • Mounts securely with heavy-duty magnets
  • Includes 2 lights and wiring harness with 4-way flat trailer connector
    • Heavy-duty vinyl protects wiring from the elements
  • Meets DOT standards


Specs:

  • Universal fit for all vehicles
  • Wiring harness length: 20'
  • Wire length between lights: 4-1/2'
  • Separate wire with 4-way for tow vehicle : 3' long
  • Bulb type: 2057 double filament
  • 3-Year limited warranty on housing and wiring only


Will These Magnetic Lights Work On My Vehicle?

These lights are a universal fit for all vehicles - however, is the roof of your car magnetic? Make sure you have a good place to put these lights or they may not be the best fit for you.



TL21RK Optronics Magnetic Mount Stop, Turn, and Tail Towing Light Kit w 20' Wiring Harness

Alternate part number: TL-21RK



This Product Fits The Following Vehicles




Customer Satisfaction Score:

Ratings & Reviews

4.6

210 reviews
Review sort icon
Stick these heavy-duty magnetic lights on the back of your car and they'll stay there. Nice and secure, these are also the easiest way to get brake and turn signals on your towed car, trailer, or cargo carrier without doing any hardwiring.

by:

This didn't work out of the box! The passenger side would not function at all. No tail, brake, or turn signal. Etrailer is issuing a return for refund. I had to leave for a camping trip, so I went to Harbor Freight and purchased an LED set for a little over half of what these cost; and these aren't LED.



by:

Used on tow car over the last year - towed at slight angle via tow-dolly. Driven 1000's of miles with this on the tow car through rough storms and strong winds - have not experienced an issue. Strong magnets have not scratched the vehicle. Would purchase again.



by:

Strong magnets. I needed an extension to plug the lights into the tow vehicle. The wires could be longer between the lights.



by:

Purchased the 10" drop/ rise receiver to make hooking up the tow bar to my jeep level. My jeep has 4" of lift on 33's and the truck is a stock 2013 dodge ram. This receiver leveled them perfectly. The light kit I purchased also works great.



by:

Installed pics



by:

Excellent service, product as promised, little modifications required to fit my Fiat 500.

Only on problem, takes a long time to wait on the phone for customer service

Jame W. profile picture

Jame W.

7/15/2021

Fantastic, wiring needs s little workcomments previously sent



by:

Plenty of cord. My only desire would be the magnets be on the back of the lights, not the bottom. But I made it work. Used this to make my bike rack euro compliant for lighting.



by:

All the products I ordered from etrailer,fit and worked excellent for me to be able to flat tow my 2015 Chevrolet Colorado behind our motorhome. I live in Canada and fast delivery on the products I ordered. I will order from etrailer again



by:

The product itself is well made and reliable. However, I didn't realize how much the wire laying across the hood of my dinghy would move while driving. This resulted in significant buffing of the surface that required several rounds of compounding to remove. I have since moved to a wireless unit.
If you plan on using this product, I would recommend running the wires under the hood or taping them down in a way that doesn't damage your dinghy's surface.



by:

I needed to move a trailer to a location where I could troubleshoot and repair the trailer lights. Worked well, good price, and reasonable shipping cost, After I had used the lights I happened to see a similar setup at Walmart which was $10 MORE than the total I paid etrailer.



by:

Attached to a bed extender for kayak hauling. Magnets are strong enough but used zip ties as extra security precaution. My vehicle is prewired for flat or round connection. Lights were all "plug and play" for me. Served my purpose very well.



by:

Looking forward to using them on a flat tow of my VW Bug.



by:

They say that a company is only as good as its employees... Well, etrailer is extremely fortunate to have someone like Shawn B. Working for them! This young lady got me out of a really frustrating predicament, and through careful listening and asking the right questions, she saved me not only a ton of money, but a whole bunch of frustration as well! My dilemma was that I had purchased a Jeep Liberty with a Blue Ox base plate, but I had a Blackhawk 2 tow bar! I thought I was going to have to go out and buy a Blue Ox tow bar to use with the Blue Ox base plate, but through careful review of my situation, and a calm analytical approach, this young lady determined exactly what I needed in the way of adapters and a towing light set up! Today, more than ever, it's all about customer service, and that is exactly what she provided for me!



by:

Nice magnetic set. I bolted small steel pieces to my ranger bumper because it is covered in plastic. An easy hack located them just wide of the tailgate so it could open with lights in place. Drove 1200 miles with no problems.



by:

After struggling with my trailer lighting system for years, I gave up and bought a portable system from etrailer. Within 5 minutes of unwrapping it, everything worked great and I am not longer spending hours trying to trouble shoot the old system. The magnets that hold the lights on the trailer are very strong, but I still use a bungy cord on each one just in case I hit a large bump in the road.

Thanks etrailer, excellent product!



by:

I purchased a Curt hitch for my 09 CRV. I also bought a wiring harness and a set of magnetic lights for attachment to vehicles. I was able to install the hitch in less than an hour. It took me 30 minutes to connect the wiring. The lights are very simple to connect and only hook up one way. The instructions included links to videos that made the job a snap. The instructions said to put the wiring inside the car by the spare tire when not in use to preserve the connector. what a great suggestion! I did not put a single mark on the car and the hitch looks great.



by:

etrailer was easy to order from and shipping was fast. However, I ordered this specific light set to fit my standard 4-way flat connection that already exists on my trailer and did not plan on doing any wiring on my truck. Unfortunately, it does not fit. I will have to buy a converter or something I guess. I emailed them with this issue asking if this light is not a standard 4-way flat and haven't received a response.
Seems to be a nice sturdy light set. Doesn't help when I can't use it, though.



by:

I got this because the lights on the trailer for my 15' Boston Whaler kept getting broken while launching. Now, I just have to hook these on before I hit the road (easily by magnet) and I can take them off before risking damage while launching. Perfect! Just make sure the wire is long enough. It just fits my little trailer, but a longer one may need an extension wire harness.



by:

Perfect, just what we needed to get our trailer home from storage so I could work on the finding the root cause for the failure of the permanent trailer lights. Now that the permanent lights have been fixed, the temporary magnetic lights are stored with the trailer sort of like a spare tire, knowing how fiddly trailer wiring can sometimes be. It's worth the small investment for the extra measure of safety in case the permanent trailer lights fail again far from home.



by:

The magnets didn't stay on the car so I ended up permanently gluing them to my roof since we tow our car behind the rv full time. Had to replace the bulbs with LED bulbs since our rv tail lights couldn't supply enough voltage to the incandescent bulbs to see them in daytime. This isn't a failure of the product but rather an undiagnosed voltage problem with our rv. With those modifications I am happy with it.



by:

I am using these for added visibility on the back of a large bike rack that pretty much stays on the car all the time. I do not suggest using the magnets as the only form of attachment as they are not strong enough to keep the lights attached when going over bumps. I zip-tied them to the frame of the bike rack. At first, I had them sticking out from the bottom of the rack, and they were fine until I went up a steep hill and one of the lights got knocked off on the road. These lights are extremely well-built because instead of snapping the light, the rather large zip-ties broke. The light still works great after the incident. I now have them sticking out the sides to give more ground clearance, and they seem to be doing fine. For my application, I had to replace the wire between the lights with a longer one, but that was not difficult and will not be necessary in a typical application. At least the lights are easy to disassemble to access the wiring. The only way these could be improved would be to add strong neodymium magnets and to make the red lenses screw on (instead of snapping on) for easier access to the bulbs for replacement. Otherwise, a perfect product.

For the record, I did not need to use the included vehicle wiring harness or splice connectors, since my application required an electronic light controller.



by:

I am very happy with this purchase. The magnets in the base of the lights keep them connected to the roof of our towed car, no wobbling! The signal wire is long enough to run through our 2019 Honda Fit and connect with our tow vehicle. After getting wet several times, the protective sticker on the bottom of the lights wore off and now the lights have left slight scratches on the roof of the car, nothing major. On the roof of our towed car, they are seen from a distance and work with the tail lights of our motor home just fine.

On occasion, we have to wiggle the wire coming out of the light to get it to work, but this is after a year’s worth of intermittent towing and I’m pretty sure we bashed them around a little. Great product at a great price, professional installation is not necessary. A little better construction and this would be a 5 star rating.



by:

The product arrived quickly and was exactly as advertised. The light kit is the perfect solution for the car I tow behind my RV, but also use by itself. I like the fact that it is totally portable, mounts high up on the vehicle for good visibility and is quick and easy to install when needed.

Ed F. profile picture

Ed F.

6/9/2018

Worked perfect. I have since gone to anew vehicle with integrated light wiring. I sold the lights to a friend and he has been happy since!



by:

works great for towing my jeep. just plug the four flat into the factory trailer wiring on the tow vehicle, set the lights on the bumper and they work perfect. the magnets are strong but the thicker the metal they are on the better they hold. steel on my bumper is thick enough for a strong hold but I tried thinner metal and the hold is weaker so you may need to add some straps

Steelhead profile picture

Steelhead

7/11/2016

one year later and still working perfect



by:

Good product.


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See what our Experts say about this Optronics Flat Tow Wiring Harness

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