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LED Backup Light w/ Flange for Trucks or Trailers - Submersible - 10 Diodes - Round - Clear Lens
Optronics

LED Backup Light w/ Flange for Trucks or Trailers - Submersible - 10 Diodes - Round - Clear Lens

Part Number: BUL11CBX
In Stock
$43.22
Retail:$86.30
You Save: 50%
Trailer Lights
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5-3/4" Diameter round. Waterproof, LED trailer light is certified for backup light function in a 2-lamp system when a pair of lights is installed. Built-in reflector. Durable polycarbonate housing and lens. Surface mount with built-in flange. Great Prices for the best trailer lights from Optronics. LED Backup Light w/ Flange for Trucks or Trailers - Submersible - 10 Diodes - Round - Clear Lens part number BUL11CBX can be ordered online at etrailer.com or call 1-800-940-8924 for expert service.
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Optronics Trailer Lights - BUL11CBX

Highlights

  • Reliable In Any Weather: Sonically sealed, waterproof housing keeps water out for lasting performance.
  • Fewer Replacements Needed: LEDs last 50 times longer and use less power than incandescent bulbs.
  • One Light, Certified Function: Meets DOT and FMVSS 108 backup light standards when used as a 2-lamp system.
  • Built-In Safety Reflector: Integrated reflex reflector removes the need for a separate reflector.
  • Simple 12V Connection: Works with standard 2-prong plug (A49PB or A45CB) for easy setup.
  • Durable Polycarbonate Build: Tough lens and housing resist impact and corrosion.

Features to know about

Bright, Efficient Backup Lighting: 10-Diode LED Output

This round 5-3/4" light packs 10 white LEDs behind a clear lens for crisp, even illumination when backing up. The LEDs are DOT compliant and meet FMVSS 108 requirements in any 360-degree position. They’re designed to last 50 times longer than incandescent bulbs while drawing only 0.26 amps at 12.8V. That means brighter light with less power use and no fragile filaments to worry about replacing.

No More Water Damage: Sonically Sealed and Submersible Design

Water can be rough on trailer lights, but this one is built for it. The housing and lens are sonically sealed into a single waterproof unit that’s completely submersible. Whether it’s backing down a ramp or driving through heavy rain, moisture stays out so the diodes and circuit board stay protected. It’s a simple fix for anyone tired of fogged or shorted lights after every trip.

Stronger Build for Everyday Use: Durable Polycarbonate Housing

The clear polycarbonate lens and tough housing make this light a solid choice for demanding environments. It holds up to vibration, impacts, and UV exposure without cracking or fading. The built-in reflex reflector removes the need for an extra reflector, keeping things cleaner and simpler on the back of your trailer or truck body.

Straightforward Installations: Surface Mount with Built-In Flange

Installing this light is simple thanks to the integrated flange and standard 2-prong connector setup (A49PB or A45CB pigtail sold separately). It uses a 4-1/2" diameter cutout and three mounting holes spaced 4-7/8" center-to-center. Just line it up, plug it in, and you’re set with a low-profile fit that looks clean and professional.

Reliable Performance Every Time: Back-Up Certified in a 2-Lamp System

When installed as a pair, these lights are certified for backup function in a 2-lamp system—giving you dependable white light coverage exactly where you need it. It’s a simple way to improve rear visibility and safety with a setup that’s efficient, rugged, and built to last for years of use.

Specs

Dimensions

  • Overall diameter: 5-3/4"
  • Depth: 1-5/8"
  • Distance between mounting holes (center on center): 4-7/8"

Technical diagram of Optronics BUL11CBX round LED backup light with built-in flange showing the 5-3/4-inch diameter and mounting dimensions.

Electrical

  • Power draw at 12.8V: 0.26 amps

Lighting

  • Diodes: 10

Warranty

  • LED warranty: Lifetime

BUL11CBX Optronics LED Backup Light w/ Mounting Flange for Utility Trucks or Trailers - Submersible - Reflex Reflector - 10 Diodes - Clear Lens

Alternate part number: BUL-11CBX





Customer Satisfaction Score:

Ratings & Reviews

4.7

292 reviews
Review sort icon
5-3/4" Diameter round. Waterproof, LED trailer light is certified for backup light function in a 2-lamp system when a pair of lights is installed. Built-in reflector. Durable polycarbonate housing and lens. Surface mount with built-in flange.

by:



by:

Jaime was amazing! She helped me find the parts I needed and kept me updated



by:

great product



by:

Item has not been installed at this time so I am unable to give you a review. I am only rating you on ordering and shipment of product in a timely fashion.



by:

I have ordered from you before and your product and service was excellent. There was one item in this order that was broken. I am contacting you to see if you will replace this item.



by:

Everything went well with the product. The guys installed the units on their truck. Very pleased with the process of ordering the lights.



by:

Great replacement part.



by:

Great product fast shipping



by:

These worked great on a 2005 Fleetwood Expedition Motorhome.



by:

Shipping was fast, part was great!



by:

Fit right in opening of original light. Super bright. Easy plugin. Great guys to buy from



by:

Excellent product. Very fast shipping.



by:

Lights arrived quickly. I used these lights to replace one existing and add a second back up light on work truck. They worked perfect and brighter than stock light



by:

Part as advertised and working perfectly



by:

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!



by:

Great replacement, very bright and nice rubber gasket included.



by:

Great Lights



by:

These Lights work great, Lot more light than the bulb light that came with my RV. I have recommended etrailer to several of my friends in our camping group.

Thanks etrailer -------- Doyle



by:

Great product very bright. I put a pair of them on my boat trailer hooked up to my back up light. They really brighten up the ramp when I launch before sun up. No more flash light out the window, I wish i had installed them years before!



by:

The package with the lights arrived a day early. I spent an hour with the help of a friend swapping them out on the back of my 1990 Peterbilt Midranger box truck. They were easy to install, work flawlessly, and look great. I replaced the lights that had used conventional bulbs, which were always problematic, due to vibration, moisture / road salt, etc. These units are sealed, so hopefully will provide long and trouble free service.



by:

Great fast



by:

After 8-9 months of installing trailer LED backup light, the rear housing fell out from the lens portion. I had to use super glue to glue the two back together. I'm worried about moisture entering the light this winter sense don't have anything to seal the joint so I guess I'll wait and see if it fails.

Craig profile picture

Craig

10/17/2017

Everything is good



by:

The customer support was above and beyond what was expected!! Thank you...

Mike L. profile picture
Etrailer Expert

Mike L.

1/20/2026

You're very welcome, Billy. I'm really glad we could help!



by:

unimaginable improvement from one ancient and lackluster incandescent bulb to 10 LED diodes-requires modification of hole but is fairly simple and worth the effort-I used it as the porch light on my '72 airstream reno-great result!



by:

Perfect fit 2017 Georgetown xl 369ds
LOOKS
100% Better ! Ty


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See what our Experts say about this Optronics Trailer Lights

  • Recommended 5-3/4" Diameter LED Backup Light
    Hey Mark, thanks for the information! The LED Backup Light w/ Flange for Trucks or Trailers item # BUL11CBX is going to be the closest option I have to your specifications. This is a 5-3/4" diameter LED back up light that mounts in a 4-1/2" diameter cutout. It has three mounting holes spaced 4-7/8" apart center on center. You can use the Right Angle 2-Wire Pigtail item # A49PB or the 2-Wire Pigtail item # A45CB to complete the installation. Do you see any part numbers on your Optronics...
    view full answer...
  • Recommended Replacement Round LED Trailer Light W/ A Chrome Bezel
    I took a look at what we carry and was able to find the: -LED Backup Light w/ Flange for Trucks or Trailers # BUL11CBX. This is a round LED light that has a 5-3/4" overall measurement, a clear lens, and a chrome bezel; which sounds like exactly what you're looking for. If this is not what you're looking for, let me know and I'd be happy to help you further. I have also attached a product overview video for you to check out as well.
    view full answer...
  • Backup Lights Similar To the Optronics 4 Inch Round LED Trailer Light # STL42RB
    The closest backup light that we carry to the 4 Inch Round LED Trailer Light, # STL42RB, is the 4 Inch Round LED Backup Light, # BUL11CBX. This is a 4 inch round clear back up light that has an overall diameter of 5-3/4 inches and a depth of 1-5/8 inches. This light will require a standard 2 prong plug, # A45CB, and has a reflector on the mounting flange.
    view full answer...
  • Does the LED Trailer Backup Light # BUL11CBX Require a 2 or 3-Prong Harness
    At first glance the picture does imply that it needs a 3-prong plug, but if you look closely there are only wires coming from two of the terminals. And the 2-prong plug like part # A45CB will fit in this setup as the two prongs of the pigtail will line up with the 2 wires of the # BUL11CBX. If you check out the picture I attached you can see how the two products would work together.
    view full answer...
    Image 1 for
  • 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...
  • Cutout Dimension Needed to Install GloLight LED Backup Light # BUL101CKB
    The hole size needed to install the Optronics light part # BUL101CKB is 4-1/2 inches. The reason this size is larger than the 4-1/4 inch diameter listed for the light is that the grommet of the light is not included in the 4-1/4 inch diameter. This would be brighter than the # BUL11CBX as well.
    view full answer...
  • Does the LED Backup Light w/ Flange for Trucks or Trailers Need To Be Replaced If Water Gets Inside
    If you have water inside the LED Backup Light w/ Flange for Trucks or Trailers part # BUL11CBX then that means the seal is broken. I recommend replacing this light as not only will it affect the luminosity of the light but it is very likely to cause a short on your trailer wiring harness. The seal can be broken by tightening the screws which hold the light too tight or just wearing out over time.
    view full answer...
  • 4 inch Clear Recessed Mount Trailer Light Recommendation
    The closest thing we have to a clear lensed version of the part # ST48RB that you referenced is the part # BUL11CBX which is clear and emits white light. This is commonly used as a backup light.
    view full answer...
  • Suitability of Optronics LED Trailer Back-Up Lamp # BUL11CBX for a Boat Trailer
    They certainly can. The Optronics # BUL11CBX is completely sealed and waterproof. They'd be perfect for a boat trailer. You'd also need either a right angle pigtail, part # A49PB or a straight pigtail, part # A45CB. Also keep in mind that although the lamps are waterproof, your trailer wiring might have junction points that aren't. This is why I recommend you unplug the boat trailer before backing into the water.
    view full answer...
  • Mounting Hole Dimensions of LED Trailer Backup Light # BUL11CBX
    The three mounting holes of the LED Trailer Backup Light # BUL11CBX that you referenced are on a circle that measures 4-7/8 inches in diameter like what is seen in the picture I attached.
    view full answer...
    Image 1 for

Do you have a question about this Trailer Light?


Info for this part was:

Employee Tyler C
Written by:
Tyler C
Employee Jameson C
Expert Research:
Jameson C
Employee Cole B
Installed by:
Cole B
Employee Brian T
Updated by:
Brian T

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