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LED Trailer Tail Light w/ Reflex Reflector - Stop, Tail, Turn - Submersible - 10 Diodes - Red Lens

LED Trailer Tail Light w/ Reflex Reflector - Stop, Tail, Turn - Submersible - 10 Diodes - Red Lens

Item # STL43RBX
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Trailer Lights STL43RBX - LED Light - Optronics
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5-3/4" Diameter round. 3-Function, waterproof LED light acts as a brake, tail, and turn signal. Built-in reflex reflector. Durable polycarbonate housing and lens. Surface mount with flange. Accepts standard 3-prong plug. Lowest Prices for the best trailer lights from Optronics. LED Trailer Tail Light w/ Reflex Reflector - Stop, Tail, Turn - Submersible - 10 Diodes - Red Lens part number STL43RBX can be ordered online at etrailer.com or call 800-298-8924 for expert service.
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  • Reviews (22)
  • Q & A (10)
  • Videos (1)
  • Photos
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Optronics Trailer Lights - STL43RBX

  • Tail Lights
  • Round
  • LED Light
  • Red
  • Surface Mount
  • 4 Inch Diameter
  • Submersible Lights
  • Optronics
  • Stop/Turn/Tail
  • Rear Reflector

5-3/4" Diameter round. 3-Function, waterproof LED light acts as a brake, tail, and turn signal. Built-in reflex reflector. Durable polycarbonate housing and lens. Surface mount with flange. Accepts standard 3-prong plug.


  • Round LED trailer tail light serves 3 functions
    • Stop light
    • Tail light
    • Turn signal light
  • Built-in reflex reflector removes the need for a separate reflector
  • Sonically sealed, waterproof housing and lens unit is submersible
  • LEDs make great replacements for incandescent lights
    • Last 50 times longer
    • More efficient - provide brighter light with less power output
    • No bulbs to replace - no brittle filaments
  • Durable polycarbonate lens and housing
  • Red lens over clear LEDs
  • Compatible with 12V DC systems
  • Surface mount with built-in flange - hardware not included
  • Accepts industry standard 3-prong plug


  • Dimensions: 5-3/4" diameter x 1-5/8" deep
  • Distance between mounting holes (center on center): 4-7/8"
  • Diodes: 10
  • Power draw:
    • Stop: 0.413 amps at 12.8 volts
    • Tail: 0.026 amps at 12.8 volts
  • Lifetime warranty on LEDs

Optronics STL43 Reflex Flange Series LED Tail Light Dimensions

Sonically Sealed, Waterproof Trailer Light

The waterproof construction of this light makes it ideal for use on trailers that may be submerged, like a boat trailer. The housing and lens are sonically sealed together to create a single unit, which means that water will not get into the light and damage the diodes or circuit board.

STL43RBX Optronics LED Combination Trailer Tail Light w/ Reflex Reflector - Stop, Tail, Turn - Submersible - 10 Diodes - Round - Red Lens

Alternate part number: STL-43RBX

California residents: click here

Video of LED Trailer Tail Light w/ Reflex Reflector - Stop, Tail, Turn - Submersible - 10 Diodes - Red Lens

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

Video Transcript for Optronics Trailer Lights - Tail Lights - STL43RBX Review

Today we're going to be reviewing part number STL43RBX. This is the four inch round red LED trailer light from Electronics. The red trailer light is going to serve three functions on trailers less than 80 inches wide, such as your stop, turn and taillight functions. It's going to feature the long lasting, super bright LED's that are a great replacement for incandescent lights. It's going to feature a multi dial design that's going to optimize your light output. You don't have to worry about replacing any bulbs or brittle filaments and these are going to be more efficient, which means they're going to provide brighter light with less power. It's got the built in reflux reflector on the mounting flange. It just goes around the perimeter of the light.

It's also going to feature a sealed, waterproof housing. It's a one piece molded plastic housing with a very durable lens. It's also got a corrosion resistant design to it and it's going to come with a rubber gasket that's included to create a weather tight seal against the mounting surface. You can see here on the back that it has a connection point. This is designed to accept the industry's standard three prong plug that is going to be sold separately.

You can find it right here at etrailer.com. If you want a right angle three wire pigtail, you can use part number A47PB, or if you want a straight three wire pigtail, you can use part number A45PB. This is Department of Transportation compliant. It meets FMVSS108 requirements and any three hundred and sixty degree position. The shape of this is round and if we take a look at the overall dimensions, it's going to give us an overall diameter of five and seven eighths of an inch and then just the light is going to measure about four and three eighths of an inch. So, again, the overall diameter, five and seven eighths and then just the light portion is going to be about four and three eighths of an inch. The depth is going to measure about one and five eighths of an inch, including the plug back there.

So you can see that there, one and five eighths. Again, it's going to feature ten diodes, which are going to be your LED's. When it comes to the power drawl, when using the stop function, it's going to use 0.314 amps at 12.8 volts and for the taillight function, it's going to be 0.026 amps at 12.8 volts. It is a flange mount installation and it does come with the rubber gasket. We're going to go ahead and hook it up to our external power source, that way you can see what it looks like with power running to it and with our overhead lights turned off. So, we just need to get all of our wires connected and then we'll take our three prong plug and we're going to stick it right in the connection point here on the back. Once you have the connectors lined up, they're just going to easily slide into one another. So you can see here that the taillight function is going to provide a nice, consistent LED signal and then when we apply our brakes, you can see how that brightens up for an even stronger signal and it's also going to function as the turn signals as well. That's going to do it for today's review of part number STL43LBX. This is the four inch round LED trailer light from Electronics.


Customer Reviews

LED Trailer Tail Light w/ Reflex Reflector - Stop, Tail, Turn - Submersible - 10 Diodes - Red Lens - STL43RBX

Average Customer Rating:  5.0 out of 5 stars   (22 Customer Reviews)

5-3/4" Diameter round. 3-Function, waterproof LED light acts as a brake, tail, and turn signal. Built-in reflex reflector. Durable polycarbonate housing and lens. Surface mount with flange. Accepts standard 3-prong plug.


I have a Newmar coach which I had a LED taillight that burnt out. I called Newmar and checked several other suppliers but no one had the one I needed. I then logged on to etrailer.com, found the exact match, ordered and received it. I’ve used etrailer in the past for towing related items but they will be my first shopping stop for all my RV needs. 597452


Spent over 8 hours looking for these same exact lights before I put my bus on the road for inauguration. Went to dozens of bus dealers, and part vendors, but i couldn't even find similar. Even called the manufacture, but they advised since i wasn't a distributor, they couldn't sell to me directly, neither did any of there distributors have it. Make a long story short, etrailer saved my butt! 336831


I bought this for my Newmar motorhome. It was a perfect fit for the old light that had only a couple of LEDs still working. It has been working flawlessly for a year now and still looks new. Highly recommended. 744514


Took old one out. This one for in with no adjustments needed. Works great. 740071


Exactly what I needed. Worked perfect and will brighten up my trailer to be seen at a good distance.Thanks 735249


Product easy to find on website. Reasonably priced and shipped as promised. I purchase all Optronics lamps from ETrailer. Only problem is this product is under the 4" lamps and outside diameter is actually 5 3/4". But was still easy to find. Great customer service when and if you need to call them. 734363




We’re upgrading a 1960 camper with LED lights throughout. These work wonderfully and are very easy to see. Good price, great service and product, highly recommended. 602330


Have found and purchased some of those hard to find items through etrailer. Found this LED tail light for my Newmar RV. Exact replacement. Delivery on time and no issues, will continue to purchase again from etrailer 577095


I found the web site easy to navigate and had the EXACT light I needed. The cost was quite reasonable, and shipping was quick. Thanks. I WILL be ordering more, now. 441676


Fast delivery. Works like new. 418230

Still working perfectly.
Gordy A - 08/09/2018



Exactly what was needed for a very good price. Easy to install. Good seal to prevent water entering. As usual, etrailer.com solved the problem. 333488


updated our motorhome from the old square type with bulbs to these round type led lights and could not be happier..bright and a more modern look...highly recommended 319990

perfect product
ray - 11/27/2017



Very good service, Fast shipping 311207


Exactly what I needed. Easy to find on the website and delivered quickly. 293422


Reasonably priced . After having them on for one year no problems. An led tailight will at 65 miles per hr illuminate an average of a car behind you seeing them come on 50feet sooner. 248263


Great product, quick delivery 202719


but they are 1 1/6 to big . but I'am going to us them. thanks 171761




Very quick delivery. Items were in good condition and were the correct parts. Company very easy to work with. 144405


great experience with etrailer for first time customer. 135496


fast great service upgraded shipping for free without even asking.excellent product 108031


Ask the Experts about this Optronics Trailer Lights

  • Installing Trailer Tail Lights with Two Wire Connections on 4-Way Wiring
    They are single function lights, so they can be used as running lights or stop/turn but not both. So for your trailer to be legal, you will need to run two on each side, one for the running light (brown wire of your 4-way) and one for the turn/stop light (green or yellow wire of your 4-way depending on side of the trailer). You will attach the power wire (green, yellow, or brown) to the red wire of your light. The white wire on your light will go to ground, so you will attach it to the...
    view full answer...
  • Mounting of Optronics 4 Inch Round Tail Light
    The Optronics Tail Light # STL43RBX does not need a bracket for mounting. It has a built in flange and includes a rubber grommet. A similar light, # STL55RB, uses a stainless steel mounting flange # A45SB. Both lights can be connected using a 3-wire pigtail, # A45PB, or # A47PB for a right angle.
    view full answer...
  • Dimensions of the Mounting Holes of the LED Trailer Stop/Turn/Tail Light # STL43RBX
    I went and pulled a LED Trailer Stop/Turn/Tail Light # STL43RBX from our warehouse and measured the mounting holes and found them to be 4-1/4 inches apart. Of the lights we carry this will be the closest matching LED light to what you have.
    view full answer...
  • Diameter of Hole Needed to Install the LED Trailer Stop/Turn/Tail Light # STL43RBX
    To install the # STL43RBX you'd need a hole diameter right at the size of 4-7/8 inches as that is the diameter of the portion of the light that would need to insert into the hole. The overall diameter is 5-3/4 inches. For a pigtail harness to wire up this light you then would want the part # A45PB.
    view full answer...
  • Is the Back of LED Trailer Stop/Turn/Tail Light STL-43RBX Exposed or Sealed
    The back of LED tail light # STL43RBX is exposed but the circuitry and diodes are sealed to prevent water from getting in and shorting out the light. This light uses a plug such as # A47PB so what you would want to do is use some dielectric grease # LT37534 on the pins before plugging it into the light. The grease will repel moisture and help prevent corrosion.
    view full answer...
  • Comparing Pedestal Mount and Surface Mount Trailer Lights
    The majority of pedestal mount lights like the Optronics Round Trailer Tail Light part # ST51RB ground though the mounting hardware and the majority of surface mount lights like Optronics Round Trailer Tail Light part # STL43RBX ground with a single wire. That said, there are pedestal mount lights that ground with a single ground wire and surface mount lights that ground through the mounting hardware. The best one for you will really just be preference as there is not really a standard...
    view full answer...
  • Available Sizes of Round Trailer Tail Lights
    We do not have an exact 2-1/2-inch match to the GloLight LED Trailer Tail Light # STL101RFB which has a 4-inch lens diameter and an overall diameter of 5-1/2-inches but we do offer other a lot of roughly similar round red lights, both LED and incandescent, that you can see on the linked page. GloLight LED Trailer Tail Light # STL101RFB is a recessed-mount type that requires a mounting hole, but among the other options are that type as well as pedestal-mount lights like incandescent model...
    view full answer...
  • Surface Mount Trailer Clearance Light Availability
    For what you are looking for a surface mount light like the part # STL43RBX would probably be a better option as it doesn't require a bracket and it does stick out a little bit.
    view full answer...
  • 4 Inch Round Tail Lights with Reflective Lens
    I do have an option for you but the Fusion LED Trailer Tail Light part # STL201RB does not have a reflective lens. I looked through all of our other 4" round tail lights and none of the ones with the included reverse light have a reflective lens. Therefore, the best option we can offer you is to separate the tail light and reverse light housing with the LED Trailer Stop/Turn/Tail Light part # STL43RBX and LED Trailer Backup Light part # BUL11CBX. These are both 4" round LED lights with...
    view full answer...
  • Does Sealed, 4" Round LED Trailer Tail Light STL42RB Also have Reflectors
    Trailer tail light # STL42RB has reflective properties but I recommend # STL43RBX. The mounting ring around this light is a reflective lens rather than just a black ring like with # STL42RB. I also recommend wiring harness # A47PB to plug into the back of the light.
    view full answer...

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Info for this part was:

Written by:
Tyler C
Expert Research:
Michael H
Updated by:
Brian T

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