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Optronics LED Trailer Light - Parking and Turn Signal - Submersible - Surface Mount - Oval - Amber
Optronics

Optronics LED Trailer Light - Parking and Turn Signal - Submersible - Surface Mount - Oval - Amber

Part Number: STL78AB
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$24.20
Retail:$27.63
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7-9/16" LED turn and parking light is waterproof, and mounts to the surface of your trailer with the built-in flange so you don't need to cut a hole in your trailer. Hardwires with the 3-wire pigtail. Great Prices for the best trailer lights from Optronics. Optronics LED Trailer Light - Parking and Turn Signal - Submersible - Surface Mount - Oval - Amber part number STL78AB can be ordered online at etrailer.com or call 1-800-940-8924 for expert service.
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Optronics Trailer Lights - STL78AB

Highlights

  • One Light, Two Functions: Provides both parking and turn signal lighting in a single unit.
  • Reliable In Any Weather: Waterproof, sealed design keeps moisture out for long service life.
  • Fewer Replacements Needed: 10 white LEDs use less power and last longer than bulbs.
  • Simple Surface Mount: Built-in flange mounts flat—no cutout required for install.
  • Low Power Draw: Uses only 0.243A for turn and 0.046A for parking at 12.8V DC.
  • Road Legal: DOT compliant for safe and compliant trailer lighting.

Features to know about

Bright, Efficient Lighting for Safer Towing: 10-Diode LED Output

Good visibility is everything when you’re towing, and this Optronics light delivers it with ten bright LEDs behind an amber lens. It handles both turn and parking functions clearly—brightening for turns and staying steady for marker use—so your signals are easy to see day or night. At 12.8 volts it only draws 0.243 amps for turn and 0.046 amps for parking, giving you strong output without adding much electrical load. That efficiency means dependable performance and less strain on your trailer’s wiring system.

No Cutting Needed: Surface-Mount Design with Built-In Flange

Mounting is straightforward with the built-in flange that lets the light sit flush against a flat surface—no hole cutting required. Just line up the four mounting holes, run the three-wire pigtail through a small opening, and bolt it down. It’s a clean, professional fit that keeps installation simple whether you’re replacing older lights or upgrading to LED for the first time.

Built to Handle the Elements: Waterproof and Fully Submersible

This light is sealed tight to keep moisture out, making it a solid choice for trailers that see heavy rain or water exposure. The polycarbonate lens and housing are tough and completely waterproof, so even if you back into the water at a launch ramp, there’s no worry about leaks or corrosion damaging the electronics inside.

Reliable Power Connections: Simple 3-Wire Setup

The wiring couldn’t be easier: white for ground, black for parking light, and red for turn signal. It’s a direct hardwire setup that works with standard 12V DC systems—no special adapters needed. That straightforward connection makes it easy to tie in matching lights like the red version (#STL78RB) if you want a consistent look across your trailer.

Compact Size That Fits Where You Need It: 7-9/16" x 3-5/16" x 3/4"

At just 3/4" thick with mounting holes spaced 7" horizontally and 2-3/4" vertically (center to center), this oval light fits neatly in tight spaces without sticking out awkwardly. The clean lines and low profile keep it protected from bumps while maintaining full DOT compliance for visibility and safety.

Specs

Dimensions

  • Overall dimensions: 7-9/16" wide x 3-5/16" tall x 3/4" thick
  • Light dimensions: 6-1/2" tall x 2" wide
  • Distance between mounting holes (center on center): Horizontal: 7" Vertical: 2-3/4"

Technical diagram of Optronics STL78AB amber oval LED trailer light showing dimensions and mounting hole layout for surface-mount installation.


Electrical

  • Compatible with: 12V DC systems
  • Diodes: 10
  • Power draw at 12.8 volts (Turn signal light): 0.243 amps
  • Power draw at 12.8 volts (Parking light): 0.046 amps

Warranty

  • Lifetime warranty on LEDs

STL78AB Optronics LED Trailer Turn Signal and Parking Light - Waterproof - 10 Diodes - Oval - Amber Lens

Alternate part number: STL-78AB





Ratings & Reviews

4.8

1756 reviews
5 Stars
(1534)
4 Stars
(144)
3 Stars
(36)
2 Stars
(17)
1 Star
(25)
Review sort icon
7-9/16" LED turn and parking light is waterproof, and mounts to the surface of your trailer with the built-in flange so you don't need to cut a hole in your trailer. Hardwires with the 3-wire pigtail.

by:

Great light and very quick shipping.



by:

I used this light to replace a turn signal on my truck. I needed it to brighter than the stock light and this light dose the job.



by:

This light is well made, but was a little disappointed because the
"stop-turn" connection only lights the center 4 LEDs brightly. I
was expecting that all 10 would be brightly lit for better visibility
on this setting.



by:

Excellent product. Used them as part of a total rewire and re-light of 48' conestoga trailer.



by:

Like the look very slimline. Makes my 2010 car dolly look like a newer version



by:

Beat price around and fast shipping!



by:

Great light at a good price but have had several that the wires broke off flush with the housing.



by:

I have order bifore from Etrailer corp. And is a real good product they have. That's why I re order some stuff for my business again. And as soon as I need more stuff I will reorder again,



by:

Very bright, great quality. Fit my 5th wheel travel trailer perfectly.



by:

These lights are perfect for updating my side marker/turn signal lights. Their slim profile and unique lighting sequence added a sleek and stylish appearance to my RV.



by:

My new light.



by:

Very nice light. Wouldn't mind if there were amber reflector ovals to go around this, similar to the red reflector ovals.



by:

I have used Etrailer twice to buy lights for custom bumpers, and the service has been excellent. The shipping is super fast and the lights are the highest quality. I will not be using anyone else.



by:

Originally purchased this exact part from a large auto parts store for $100 and they needed 2-4 weeks to process this "special order part". I cancelled that order as soon as I found it here for 1/5 of the cost and It arrived really fast, an easy buying process, and the follow up customer service was great. We are installing this part next month. If anything happens to go wrong with the light, I have a lot of faith that CS will be nothing short of amazing in helping us resolve the problem.



by:

These lights were to replace the ones not working on my boat trailer. You would think that the skeeter dealership could either have them in stock or be able to order. Thank you for being there etrailer.



by:

My lights came in before scheduled, as usual, and were in perfect condition. No defects. I bought two of them, along with a set of the red versions to put on my headache rack. They are very bright, much brighter than my incandescent stock tail lights. The only thing I don't like is how you can see the circuit board in them, but that's only up real close.



by:

Worked perfectly.



by:

E trailer is a fantastic place to shop. The selection and price and even more important I like to call my orders in , their reps who I talked to were all knowledgeable, very helpful and customer friendly.

I even added to my order a day later and they went the extra mile to ensure everything went out in one package.

These are great lights we want to be sure they had turn signals as when towing it gives us the confidence to know everything is working well.
We needed submersible and LED and wanted to be sure they fit the trailer and would work no matter the surface material, and were easy to install.
I wish I had known of e trailer years ago, I am a customer for life.



by:

Quality product. Well built and seem to be quite durable compared to the old single bulb style. I installed these on the sides of my trailer for added visibility at night and also on the back of my van to aid the factory hazard flashing lights.



by:

STL78ab 6-1/2" Oval LED Trailer Turn Signal and Parking Light, Flange Mount, 10 Super Diode: Nothing wrong with this light, but now that I purchased the Miro-Flex Technology with the new generation of LED, its hard to have these as my favorites anymore. I did purchase the Reflective ring to put around it, and I like that product, it adds to this light and coves up the black frame with a highly reflective amber reflective area.



by:

Replacement for old marker lights that had been discontinued on my class a rv, they look nice are bright and an improvement.

James profile picture

James

5/10/2019

All the products are performing great...........very happy



by:

It is a great product. I like for the streamline and isn't bulky. It will used on the golf cart to run on road at times for safety.



by:

Used for turn signals on a side by side my primary use vehicle. Often used flashers. One year service and working great for me. Bright. EZ install.



by:

I mounted these behind a plate to replace the cloudy front lights on my truck. Much better look. They were a little lighter weight than I expected but the build quality looks good.



by:

Worked great as a replacement for OEM that was no longer available for RV. I also replaced the back side marker lights so the front and back matched.
Pat C did a great job in completing my order with substitution for out of stock resistor.


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