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Heavy Duty Magnetic Tow Lights - 25' Wiring Harness with 4-Way Flat Trailer Connector

Optronics Trailer Lights

ratingratingratingratingrating (12 reviews)

Code:   TL21RK


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Shipping Weight: 3 pounds


Optronics Trailer Lights - TL21RK

Get lights for towing your vehicle without splicing into its wiring. Magnetic light kit provides a pair of stop, turn, and tail lights. Mounts using large, heavy-duty magnets for increased stability. Plugs in at rear of your motor home.


  • Light kit allows you to bypass your vehicle's wiring to provide temporary lights for your towed car
    • Can also be used as trailer lights
  • 2 Red lights act as brake, tail, and turn signal lights
  • Magnetic bases let you easily mount lights on trunk or roof of your car
    • Large, heavy-duty magnets provide excellent stability
  • Wishbone-style wiring harness can be easily routed beneath car
  • 4-Pole flat connector on harness is designed to hook up to your RV's 4-way trailer connector
  • Separate, 3' long harness with 4-way can be wired into tow vehicle or RV if no trailer connector is present
    • Includes quick-splice connectors for simple installation
  • Department of Transportation compliant


  • Wiring harness length: 25'
  • Wire length between lights: 4-1/2'
  • Separate wire with 4-way for tow vehicle: 3'
  • Bulb type: 2057 double filament
  • 3-Year limited warranty on housing and wiring only

A towed car is required by law to have functional brake and signal lights that illuminate at the same time as the brake and signal lights on the RV that is towing it. Most wiring kits require you to splice into your vehicle's electrical system to install diodes, but doing this can void your manufacturer's warranty. You also run the risk of making a mistake during installation that could result in potentially damaging electrical feedback. Magnetic tow lights eliminate this problem because they bypass your car's electrical system entirely and leave your wiring intact. Just mount the lights on your vehicle's trunk or roof with the heavy-duty magnetic bases. Then run the wiring harness up to the front of your towed car, across your tow bar, and then connect it to the 4-way flat on your motor home or tow vehicle. If your tow vehicle doesn't have a 4-way, an adapter is required.

This kit includes a 25' long wishbone-style wiring harness with a 4-way flat connector on the end. A separate 3' wiring harness with a 4-way plug can be used to install a 4-way on your tow vehicle or RV if it does not already have a trailer connector. Quick-splice connectors are included if needed. A 4-1/2' long harness connects both lights, giving you enough slack to position the lights where you want them.

TL-21RK Optronics Magnetic Mount Stop, Turn, and Tail Towing Light Kit w 25' Wiring Harness

Video of Heavy Duty Magnetic Tow Lights - 25' Wiring Harness with 4-Way Flat Trailer Connector

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

Video Demo Optronics Trailer Lights TL21RK
Optronics Trailer Lights TL21RK Review

Video Transcript for Optronics Trailer Lights TL21RK Review

Today, we're going to review Part Number TL21RK. These are the Optronics Magnetic Mount Stop, Turn and Tail Towing Light Kit with the 20-foot Wiring Harness. This is a temporary magnetic towing light kit that includes the two stop and turn tail lights, the 20-foot trailer wiring harness and a stand-along three foot long four way vehicle-end connector, in case your vehicle doesnt have one. It comes with the quick connectors to attach the four-way to the vehicle if needed in the instructions. This does come with a limited three year warranty. Now, that warranty does exclude the bulbs.

It is magnetic mount, so you can just attach this to, if youre towing a vehicle, if youtr flat-towing the vehicle and you dont do it very much and you just need to use the lights a few times, you can use this magnetic mount. You can use it on the trailer if you have a trailer that doesnt have lights and you might need to use it at night. Basically, this magnetic mount, I have a piece of metal here. You can see it will attach to it and stays pretty firm to it. Its got a good pull to it, pretty hard to detach it.

You just put one of these on each side. The cord here is about four-foot, so they will spread out four-foot width. Now, I do want to show this does come with this 20-foot wiring harness. It has a trailer connector that where you plug into the vehicle-end four-way if your vehicle has one or if you attach this one to it. To give example of the brightness of the lights, I have a four-way vehicle-end connector attached to a power source.

Im going to give you an idea. Ill plug this in; we turn on the tail lights. This is what the tail lights would look like. Now, Im going turn off the overhead lights to give you an idea how bright they are in somewhat darkness. Then if you apply the brakes, as you can see, thats with the brakes and if we do a turn signal, I want to give you an idea of just the turn signal.

Thats how the turn signal would look like. Now, well go ahead and turn off or turn back on the overhead lights. That should do it for the review of the Part Number TL21RK. This is the Optronics Magnetic Mount Stop, Turn and Tail Towing Light Kit with the 20-foot Wiring Harness.

Customer Reviews

Heavy Duty Magnetic Tow Lights - 25 - TL21RK

Average Customer Rating:  ratingratingratingratingrating4.8 out of 5 stars   (12 Customer Reviews)

- TL21RK

ratingratingratingratingrating by: Doug Q05/28/2013

Is this review helpful?

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.82108

- TL21RK

ratingratingratingratingrating by: Nick08/25/2012

Is this review helpful?

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.53035

- TL21RK

ratingratingratingratingrating by: Michael L.01/06/2012

Is this review helpful?

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.29217

- TL21RK

ratingratingratingratingrating by: Doug M.04/07/2014

Is this review helpful?

as always, etrailer shipped a great item very quickly. It was exactly what they stated it was. Looking forward to a road trip to take full advantage of the light kit.124111

- TL21RK

ratingratingratingratingrating by: jim f.10/22/2013

Is this review helpful?

Totally what I was hoping it would be. The magnets seem very strong.104681

- TL21RK

ratingratingratingratingrating by: scott08/27/2013

Is this review helpful?

awesome product with simple plug and play install. 97127

- TL21RK

ratingratingratingratingrating by: John07/14/2013

Is this review helpful?

Wiring not long enough to reach back of towing vehicle. Plug did not fit. Had to trim plastic okug to make it fit89468

- TL21RK

ratingratingratingratingrating by: Jon02/08/2013

Is this review helpful?

Easy Transaction, quality product, super fast shipping. A+ all the way.65455

- TL21RK

ratingratingratingratingrating by: Bo01/03/2013

Is this review helpful?

Everything needed for my application. Easily moved from tow dolly mount to fender of vehicle being towed.62410

- TL21RK

ratingratingratingratingrating by: john m11/01/2012

Is this review helpful?

products look great; the package arrived in record time too. Will definitely be a repeat customer. 58610

- TL21RK

ratingratingratingratingrating by: Robert O04/17/2012

Is this review helpful?

I was surprised that it was shipped as quick as it was. The lights were a better quality then I thought they would be. I will use the site when other towing accessories are needed. Thanks for the speedy service and great quality product.37507

- TL21RK

ratingratingratingratingrating by: Leroy_Q06/08/2010

Is this review helpful?

Easy to use and works great Purchased in an emergency towing situation and they worked out great. Was easy to hook up and use. 3115

Ask the Experts about this Optronics Trailer Lights
Expert Answers about Heavy Duty Magnetic Tow Lights - 25' Wiring Harness with 4-Way Flat Trailer Connector - TL21RK                                            Do you have a question about this Trailer Lights?

  • Are Bulbs Included with the Magnetic Mount Stop, Turn and Tail Towing Light Kit # TL21RK
  • Yes, the bulbs are included in the Magnetic Mount Stop, Turn and Tail Towing Light Kit with 20 foot Wiring Harness, item # TL21RK. The statement, Limited 3-year warranty - excludes bulbs, is referring to the fact that the bulbs are not warranted for three years. If replacements are needed the Replacement Light Bulb # 2057, item # A2057B, is the correct part. You can gently pry the rear black plastic cover, on the back of the light, off with a small screwdriver.
    view full answer...

  • Troubleshooting Magnetic Light Kit for Blinkers Not Working Correctly
  • I would check the connector of your tow vehicle and test it for voltage with a circuit tester like our # 3808. A magnetic towing light kit like the Optronics Tow Bar Lights # TL21RK that you referenced should be able to provide any and all tail light functions when installed correctly. It sounds like the problem is in the trailer connector of your tow vehicle. Using the # 3808 you should test for voltage on the 4-way on all of the circuits to make sure that your vehicle is wire correctly. I a
    view full answer...

  • How Strong are the Mounting Magnets on Optronics Towing Lights # TL21RK
  • Describing the strength of the magnets used on the Optronics Magnetic Mount Tail Lights would be fairly difficult, as magnet strength is pretty subjective. The magnet on one of the lamps is strong enough to suspend a 6 pound ball mount, as you can see by watching the short video I produced for you. Hopefully, this will give you an idea of how strong the magnet is. The thickness of the metal the magnetic light is attached to will also have a bearing on how well the magnet adheres to the ve
    view full answer...

  • Can the Wiring on Magnetic Mount Stop, Turn and Tail Towing Light Kit Be Extended
  • You can add additional wire if you need to on light kit # TL21RK. You can cut and splice in the appropriate length of bonded 4-wire, # 16-4B-1. It is sold in 1 foot increments so if you needed 10 feet you would enter 10 in the quantity box. And you can use butt connectors, # 05731-5, to make the splices. I do recommend wrapping the connections in electrical tape to further protect them. Another option that will not require cutting and splicing is to use extension loop # RM-300150-00. It is 6
    view full answer...

  • Need Base Plates and Magnetic Tow Light Kit for 2007 Mini Cooper Convertible
  • I reviewed an online copy of the owners manual for the 2007 Mini Cooper. Page 114 indicates that the manual transmission model may be flat towed (with the gear shift in neutral) but that the automatic transmission version cannot be flat-towed without causing transmission damage. The automatic must be towed with the front wheels up off the ground as with a tow dolly like RoadMaster # RM-2000-1. If your 2007 Mini Cooper convertible is a manual we offer Roadmaster Base Plates # 521876-1. These f
    view full answer...

Info for this part was:

Photos by:
Theodore B

Expert Research:
Michael L

Written by:
Tyler C

Expert Research:
Robert G

Expert Research:
Michael H

Updated by:
Tricia G

Expert Research:
Jameson C

Expert Research:
Adam R

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