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Optronics LED Trailer Tail Light - Stop, Tail, Turn - Submersible - 21 Diodes - Round - Red Lens

Optronics LED Trailer Tail Light - Stop, Tail, Turn - Submersible - 21 Diodes - Round - Red Lens

Item # STL55RB
Our Price: $16.87
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Optronics Tail Lights - STL55RB
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4-5/16" Diameter round. 3-Function, waterproof LED light acts as a brake, tail, and turn signal. Durable polycarbonate housing and lens. Recessed mount with grommet (sold separately). Accepts standard 3-prong plug. Great Prices for the best trailer lights from Optronics. Optronics LED Trailer Tail Light - Stop, Tail, Turn - Submersible - 21 Diodes - Round - Red Lens part number STL55RB can be ordered online at or call 1-636-306-4830 for expert service.
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  • Reviews (66)
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Optronics Trailer Lights - STL55RB

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

4-5/16" Diameter round. 3-Function, waterproof LED light acts as a brake, tail, and turn signal. Durable polycarbonate housing and lens. Recessed mount with grommet (sold separately). Accepts standard 3-prong plug.


  • Round LED trailer tail light serves 3 functions
    • Stop light
    • Tail light
    • Turn signal light
  • 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
  • Recessed mount with grommet (A45GB - sold separately)
    • Mounts in any 360 degree position
  • Accepts industry standard 3-prong plug


  • Dimensions: 4-5/16" diameter x 1-1/2" deep
  • Diodes: 21
  • Power draw at 12.8V:
    • Stop/turn: 0.208 amps
    • Tail: 0.013 amps
  • Lifetime warranty on LEDs

Optronics STL55 Series High Count 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.

Recessed-Mount Light

Recessed mount light

Recessed-mount trailer lights install underneath a housing or a grommet (A45GB - sold separately). These lights will extend into the mounting surface and require that a hole be cut into your trailer.

STL55RB Optronics High Count LED Combination Trailer Tail Light - Stop, Tail, Turn - Submersible - 21 Diodes - Round - Red Lens

Alternate part number: STL-55RB

California residents: click here

Customer Satisfaction Score:

Customer Reviews

Optronics LED Trailer Tail Light - Stop, Tail, Turn - Submersible - 21 Diodes - Round - Red Lens - STL55RB

Average Customer Rating:  4.8 out of 5 stars   (66 Customer Reviews)

4-5/16" Diameter round. 3-Function, waterproof LED light acts as a brake, tail, and turn signal. Durable polycarbonate housing and lens. Recessed mount with grommet (sold separately). Accepts standard 3-prong plug.


Easy to install and was an exact match to my trailer original equipment. This light has triple the LEDs in it so the lighting to the rear of the trailer is much brighter and safer.

Very impressed. Everyone commented on the brightness of the led brake lights. If needed, I would purchase again.
Donald - 05/21/2022


Would be 5 stars except that they were hard to install in the grommets. Finally had to grind the ridge off to get them to fit into the grommets... Great once installed!


Your service was great, but I ordered the wrong one so have to try agai


Best lights for boat trailer that I have found. Even with frequent submersing last around 5 years.

They are doing fine. No issues.
John M - 01/22/2022


I’m so happy I was able to find the trailer light that fit perfectly on my 1977 holiday rambler. Thank you so much


These are fantastic. I really like the brightness, how they install (quick connector plug) and the fact that they are sealed. They mount in gasket that also provides shock protection and a good tight fitting. Had no issues with either one to date. Would buy these for all future trailers. Looks great, works great.


Product was exactly what I was looking for as I was replacing a 4" taillight on a truck camper. Since the 4" lights are fairly standard, I was able to quickly replace the bad ones. Staff went out of their way to offer me a more effective shipping solution that what I had chosen on my own including taking the time to personally contact me. My first purchase with them, very satisfied.


The lights are bright and easily seen. A wiring harness is not included and I had to order independently. Also, no screw to secure the ground wire. I was able to adapt these lights to an old trailer with different trailer light housings fairly easy.


received the lights in perfect condition and extremely quick. they are perfect for my new tail lights which will be mounted to a piston for my rat rad truck.

mike p - 11/07/2017


This light fit into my new used truck camper like a pro. has all my future business of this sorts. The product was accurately described and the website is as easy to navigate as any I can think of.


The product arrived quickly and was just as described. My trailer is older and I was having trouble finding replacements for the tail lights. Their sales rep, Cathy T., was knowledgeable and friendly. The next time I need parts for my horse trailer, I will go directly to etrailer.


The brightness is great! It is a little hard to install.


I got 2 of these jewels for my trailer lights. They are very bright and look great. I plan on ordering 2 more.


Was very pleased,I also need the trim to cover the screws on rail on the side of my trailer


Bright and easy to install


Great light


We replaced all 4 tail lights on our 5th wheel trailer with LED lights. They were easy to replace and work great.


Fit perfect easy to install replaced 20 year old trailer lights LED. BIG Difference!


Really dresses up the tailight


I bought these lights to replace some that I already had in use, that had over half of the diodes burned out. The old lights were over 10 years old. I hope these new ones last as long.


Great product fit exact into existing g asket


Correct light to replace my trailer lights. Great product


good product, looks nice lit and easy to install, oredered on Sunday received on Friday. Took me approx. 1 hour to install all 15 lights on my dump trailer.


Quality LED lights with pigtails! Fit great and works well.


The product was exactly what we expected, but the AMAZING thing was that it was on our doorstep the day after we placed the order!!! Couldn't be happier!

Show More Reviews

See what our Experts say about this Optronics Trailer Lights

  • Replacement 4 Inch Round Tail Lights With Stop/Turn/Tail Functions
    We have many 4 inch round tail light options like the Peterson Round Trailer Tail Light, 2 Stud Mounting, Right Hand # 431800. We also have LED options like Optronics Sealed, 4" Round, LED Stop/Turn/Tail light, 21 Diode - Red # STL55RB. I've linked the page to our 4 inch round tail light options for you that have the stop/turn/tail functions.
    view full answer...
  • Replacement Tail Light for 2009 Ranger Boat Trailer
    Sometimes it is possible to replace a broken trailer light with one that uses a different type of installation but since we offer a very wide range of lights you may very well be able to find an exact OEM-style replacement. It sounds like you have a light like # STL42RB which has a 3-hole mounting flange. I linked our main page for trailer tail lights of all shapes and sizes. On the page you can simply click on the filters for light shape, light type (LED or standard bulb), lens color,...
    view full answer...
  • Can Trailer Taillight STL55RB Replace Incandescent Bulb on Older Vehicle
    If you wanted to install the # STL55RB in place of the bulb you have now on your vehicle you certainly could but there isn't a direct adapter available. You'd basically need to remove the socket you have now so that you could wire the harness part # A47PB to it which is what plugs into the # STL55RB.
    view full answer...
  • Replacement Tail Light For Forest River Georgetown XL RV
    I'd be happy to assist you. It sounds like you need the Sealed, Flush Mount Tall Rectangle LED Trailer Stop, Turn and Tail Light, Grommet and Plug, 12 Diode # STL34RB but most of the pictures I see have round tail lights like the Sealed, 4" Round, LED Stop/Turn/Tail light, 21 Diode - Red # STL55RB. If this is not the correct part, then send me a photo with the measurements of the light and we will get you what you need. The numbers and letters that are actually printed on the light are...
    view full answer...
    Image 1 for Image 2 for Image 3 for
  • Bright LED Trailer Taillight Recommendation for Replacing 4 inch Trailer Light
    The Optronics LED Trailer Tail Light # STL55RB is going to the brightest option we have and will work great for your application. Each of these has 21 diodes in it which means it will put out quite a bit of light. The people behind you will have no problem seeing them! You'll also need the grommet part # A45GB to install the light as well as the pigtail part # A45PB. The mentioned light does not have reflectors but is very bright, the next brightest option that does have reflectors is...
    view full answer...
  • 2 inch and 4 inch Diameter Recess Mount LED Clearance Light Recommedation
    For the 2 inch light you would want the part # MCL55RB with the grommet part # A54GB and pigtail part # A46PB. For 4 inch we have the part # STL55RB. You would need the grommet part # A45GB and the same pigtail # A54GB. I wish we had a 3 inch option, but you may be able to enlarge the 3 inch holes to match the 4 inch ones.
    view full answer...
  • How Does a Trailer Light Mount in the Buyers Products Light Box 337LB663
    The Buyers Products Tail Light Mounting Box - 4" Round Hole # 337LB663 is designed to be used with something like the Rubber Grommet for 4" Round Trailer Lights # A45GB and Optronics LED Trailer Tail Light - Stop, Tail, Turn - Submersible # STL55RB. The light will snap into the grommet, which will then snap into the mounting box. The wires of the 3-Wire Pigtail for Optronics Trailer Lights # A45PB will need to be run through the small hole that is drilled into the box, but this can be a...
    view full answer...
  • Replacement 4 Inch Reverse Lights to Replace Truck Lite Stop Turn Lights
    If the cut out diameter of your vehicle is 4-1/2 inches then you can install the part # STL55RB in place of what you have with the grommet part # A45GB. For a similar clear version of this light you would want the # BUL43CB.
    view full answer...
    Image 1 for
  • Recommended Grommet for Optronics 4 Inch Round LED Light # STL55RB
    Both the Rubber Grommet # A45GB and the Notched Rubber Grommet # A45GNB that you referenced will fit and work well with the Optronics 4" Round LED Light # STL55RB. The only difference between the two grommets, as you mentioned, is the notched cut out in the lower portion of the unit. This is not necessary for wiring or fitment, but it will allow for a bit of an easier install.
    view full answer...
  • Recommended Trailer Tail Lights for 4.25 Inch Opening
    The LED Trailer Tail Light # STL42RMB has screw mounting holes that are 4-1/4 inches on center. The smallest hole this light will fit is 4 inches. You will have difficulty mounting this light as your opening matches the mounting hole locations so you won't get proper hold. You may want to use the Rubber Grommet for 4" Round Trailer Tail Lights # A45GB along with the # STL55RB which won't use any screws to mount. You will also want the 3 wire pigtail # A45PB.
    view full answer...
    Image 1 for
  • 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...
  • 4 Inch Round Trailer Tail Light Cutout Size
    The closest to 4 inch round lights we have is the Optronics LED Trailer Utility Light # BUL43CB or Trailer tail Light # STL55RB which are actually 4-5/16" diameter x 1-15/16" thick. These are designed to fit the Rubber Grommet for 4" Round Trailer Lights - PVC # A45GB which requires a 4-1/2 inch diameter cutout. You will also need wiring pigtail # A47PB. If you are interested in the Optronics Trailer Tail Light - Stop, Turn, Tail - Incandescent - Round - Red Lens # ST40RB you asked from...
    view full answer...
    Image 1 for
  • Red and White LED Trailer Lights
    We do have the lights that you need, but not necessarily in a kit. For the red you can use the Optronics LED Trailer Tail Light # STL55RB (x2) along with the Rubber Grommet for 4" Round Trailer Lights # A45GB (x2) and the 3-Wire Pigtail for Optronics Trailer Lights # A45PB (x2). For the white you can use the GloLight LED Backup Light w/ Grommet and Pigtail # BUL101CKB (x2) which includes the grommet and wiring.
    view full answer...
  • Recommended LED Replacement Lights for 2005 Damon Daybreak Motorhome with Load Resistors
    The Sealed, 4" Round, LED Stop/Turn/Tail light, 21 Diode - Red # STL55RB will work great on your motorhome. You will simply need to use the wiring pigtail # A47PB for each light. You will simply need the butt connectors # DW05744-5. On some vehicles, when switching to LED lights, there is a load resistor needed to prevent hyperflashing but this is not always needed. If you do end up needing a load resistor, I recommend LED Light Bulb Load-Resistors # DI34ZR. You can get these already...
    view full answer...
  • Which Trailer Tail Lights Work With 4" Trailer Light Mounting Bracket BK45BB
    I would be happy to help! The Trailer Light Mounting Bracket for 4" Trailer Lights, Steel - Black Powder Coat # BK45BB you were looking at works with 4" round lights so I recommend the Optronics LED Trailer Tail Light - Stop, Tail, Turn - Submersible - 21 Diodes - Round - Red Lens # STL55RB. You will also need Rubber Grommet # A45GB and Wiring Pigtail # A45PB. I recommend using heat shrink butt connectors # DW05744-5 for a weather tight connection. I included videos of the products...
    view full answer...

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Info for this part was:

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Expert Research:
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Updated by:
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