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LED Combination Trailer Tail Light - Submersible - 8 Function - 21 Diodes - Square - Driver Side
Optronics

LED Combination Trailer Tail Light - Submersible - 8 Function - 21 Diodes - Square - Driver Side

Part Number: STL3RB
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$33.74
Retail:$37.32
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6-1/8" x 4-9/16" Square. Waterproof LED tail light acts as brake, tail, turn, side marker, side reflector, rear clearance, rear reflector, and license plate light for trailers over 80" wide. Stud mount - includes hardware. 23 Diodes. Great Prices for the best trailer lights from Optronics. LED Combination Trailer Tail Light - Submersible - 8 Function - 21 Diodes - Square - Driver Side part number STL3RB can be ordered online at etrailer.com or call 1-800-940-8924 for expert service.
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Optronics Trailer Lights - STL3RB

Highlights

  • One Light, 8 Functions: Provides stop, tail, turn, side marker, clearance, reflectors, and license plate light.
  • Reliable In Any Weather: Sonically sealed, waterproof housing and lens keep water out so it stays lit.
  • Fewer Replacements Needed: LEDs last 50 times longer and draw less power than old bulbs.
  • Clear Visibility: 21 bright diodes deliver strong, even illumination for safe towing.
  • Simple Mounting: Stud mount design with included hardware makes installation straightforward.
  • Built to Fit Wide Trailers: Meets lighting needs for trailers over 80" wide with integrated clearance lights.

Features to know about

Brighter and Longer-Lasting Lighting: 21-Diode LED Power

This square LED combination light packs 21 diodes that deliver bright, even illumination for stop, tail, and turn functions. At 12.8V, it draws just 0.268 amps for stop/turn and 0.059 amps for marker, so it’s powerful yet efficient. LEDs last up to 50 times longer than incandescent bulbs, meaning no burnt-out filaments or dimming over time. It’s a clean, consistent light that keeps you visible without draining your power source.

No Worries About Water Damage: Fully Submersible and Sealed

If your trailer ever meets rain, road spray, or even full submersion, this light is ready for it. The housing and red acrylic lens are sonically sealed into one waterproof unit, keeping moisture away from the diodes and circuit board. That protection makes it ideal for wet or harsh environments where other lights might fail. Once mounted, there’s no concern about leaks or corrosion inside the light body.

All-in-One Functionality: Eight Lighting Features in One Unit

This single light covers eight essential functions—stop, tail, turn, side marker, side reflector, rear clearance, rear reflector, and license plate illumination. Everything is built in to meet lighting requirements for trailers over 80" wide without adding separate reflectors or secondary lights. It simplifies wiring and mounting while giving full coverage from one compact package.

Flatbed trailer over 80 inches wide with combination LED tail lights mounted at each rear corner for rear clearance and visibility.

Straightforward Mounting: Stud-Mount Design with Included Hardware

The surface mount setup makes installation simple and solid. The light measures 6-1/8" long by 4-9/16" tall by 2-7/8" thick with 2" between the center of the mounting studs. The three-wire design hardwires directly to 12V DC systems—straight power connection without extra adapters or plugs. Durable plastic construction holds firmly in place once mounted for a clean fit that stays secure on the road.

Built for Compliance and Reliability: DOT Approved Performance

This combination tail light is DOT compliant, so it meets all federal visibility standards when properly installed on each rear corner of a trailer over 80" wide. With its built-in license plate light and reflector functions, it checks every box for safety while maintaining the low-maintenance reliability of modern LED design.

Specs

Configuration

  • Driver side: STL3RB
  • Passenger side: STL2RB (sold separately)

Dimensions

  • Length: 6-1/8"
  • Height: 4-9/16"
  • Thickness: 2-7/8"
  • Distance between mounting studs (center on center): 2"

Dimensional drawing of Optronics STL3 Series LED combination trailer tail light showing measurements and mounting stud spacing for installation reference.

Electrical

  • Power draw at 12.8V (Stop/turn): 0.268 amps
  • Power draw at 12.8V (Marker): 0.059 amps
  • Voltage: 12V DC systems
  • Wire gauge: 20 gauge

Lighting

  • Diodes: 21
  • Functions: Stop, tail, turn, side marker, side reflector, rear clearance, rear reflector, license plate

Warranty

  • Lifetime warranty on LEDs

STL3RB Optronics LED Combination Tail Light for Trailers Over 80" Wide - Submersible - 8 Function - 21 Diodes - Square - Red Lens - Driver Side - Left Hand

Alternate part number: STL-3RB





Customer Satisfaction Score:

Ratings & Reviews

4.8

3475 reviews
5 Stars
(2974)
4 Stars
(347)
3 Stars
(65)
2 Stars
(32)
1 Star
(57)
Review sort icon
6-1/8" x 4-9/16" Square. Waterproof LED tail light acts as brake, tail, turn, side marker, side reflector, rear clearance, rear reflector, and license plate light for trailers over 80" wide. Stud mount - includes hardware. 23 Diodes.

by:

I bought LED lights (tail,stop,turn) for my car trailer. A great improvement over the old lights.



by:

Haven't installed yet but seems to be great quality. I ordered from E trailer via telephone and Marcia went above and beyond answering my questions and even contacting the manufacturer to get the info I needed. Will definitely order from E trailer again!



by:

Does the job very well. The side marker extends out more than I like, but I understand that this is a design that replaces rear and rear side markers on over 80" wide trailers.



by:

Nice and bright. A direct fit for my snowbear trailer!



by:

Direct replacement item.
Easy to locate
on line and order.
Quick order receipt and shipping info.
Delivered earlier than expected.
Good follow up - would order from etrailer.com again.



by:

Perfect replacement tail light for my t railer.

Kevin profile picture

Kevin

8/21/2021

Its been a year and thousands of miles later, still working as it should. All lights still burning.



by:

Great replacement part. The extended side lamp makes it easy to see in side view mirrors looking back. Only wish the grounding wire was internal and tapped into the mounting screw.



by:

I just installed and tested them. They installed quite easily.
They are nice looking and bright.
They seem to be well built.
We'll see how these are after a couple years.
My last set were also L.E.D. type (but not this brand).
I thought, barring any accidents, they would last many years.
They didn't.
They did last longer that the incandescent type though.
Vibration seems to be the biggest enemy for trailer tail lights.



by:

The LED trailer lights arrived as promised. It was easy to install and has been a huge improvement over the original lights installed by the trailer's manufacturer.



by:

Had a damaged light on my trailer and decided to go with LED this time, so I replaced both sides. Very easy to install. Wires were color coded and matched my harness. Looks and works great. I was not able to find the LED in 80" plus size in local store for some reason. Only could find the 80 and under model. etrailer came through for me. Would buy from them again.



by:

My husband has a mowing business and needs his trailer about every day. When a light gets brakes or goes our he needs it replaced as soon as possible, therefore, I need to order a replacement from a company we can depend on.



by:

All ordered items worked great. Love the LED tail lights. Didn't have any problems fixing the trailer thanks to the many technical articles I found on etrailer. Not sure what happened with UPS shipping since I got notified that the parts had shipped on Saturday but didn't get them till Wednesday evening (paid extra for 3 day shipping), but definitely recommend ordering from etrailer.



by:

Quality part



by:

These fit Carryon trailers from [tractor store]. They are excellent bright lights. Unfortunately for me they aren't unbreakable, but I eventually cut that too-close Valencia orange tree down. Yes, a chainsaw was the solution to my trailer light "problem".



by:

I bought these as a replacement for ones on a car trailer. The factory ones died after a few months.

The fit and look great.

I have ordered several lights and lenses from etrailer.

In stock, good price and fast shipping .. what more needs to be said.



by:

Works great- just as advertised!



by:

They work great. LED's are such a good way to go for trailer lights.

Bruce T. profile picture

Bruce T.

11/15/2017

They are working great. I am a big fan of LED light for trailers.



by:

Awesome product from an awesome store. Product arrived just as described. Packing was great and looks just like I expected them to from the etrailer.com web site. Will get them installed and reviewed further. Hopefully this time, some bonehead won't back into my trailer in the parking lot of the boat ramp. Thanks etrailer for the great service.

Ted profile picture

Ted

8/4/2016

A year later and just as good as the day I installed them. Thanks etrailer.com



by:

Great LED Light for Utility trailer use over 80 inches wide. Combination light saves the cost of a stand alone side marker / identification light.

Jim profile picture

Jim

5/2/2017

LED lights work great, look good , are very bright and reliable. Very satisfied.



by:

works great and was a direct bolt on replacement for my tail light

Michael profile picture

Michael

3/25/2025

Still work great. Havent had any issues.

Kate F. profile picture
Etrailer Expert

Kate F.

3/25/2025

@Michael Glad things are lit up as they should Michael!


by:

I needed this replacement trailer light asap and they got it to me in less than 24 hours ! It was super easy to hook up and worked perfectly ! I was really impressed , going to order more from this company.



by:

Excellent service and shipping. Will use etrailer again for my trailer needs.



by:

Just received and installed this light today. Replaced 7 year old lights on my utility trailer hoping to not have to mess with light bulbs anymore. The light works as it should, it's nice and bright, arrived in a reasonable time frame, was packaged well, and hopefully will last. I have ordered many items from etrailer and have never had a problem.



by:

Bright works as it should. You can’t ever go wrong with Etrailer and customer service…



by:

This light burns bright and no issue with leaks. Initial issue with power getting to bulbs which ended up being the installer's (my) error. :)


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See what our Experts say about this Optronics Trailer Lights

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    Hey Mike, we have an LED version of the part # ST3RB with the part # STL3RB for the driver side and then the part # STL2RB for the passenger side. Switching to LED for better reliability?
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Info for this part was:

Employee Jacob T
Video Edited:
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Employee Adele M
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Adele M
Employee Laura H
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Employee Wilson B
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Employee Brian T
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Employee Dustin K
Video by:
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Employee Cole B
Installed by:
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