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Optronics Back Up Light - Round - Clear Lens

Optronics Back Up Light - Round - Clear Lens

Item # BU41CB
Our Price: $9.90
Trailer Lights
Orders above $50 qualify for Free Shipping
Shipping Weight: 0.49 lbs
In Stock
Trailer Lights BU41CB - Incandescent Light - Optronics
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5-3/8" Round. Incandescent trailer light functions as a back-up light. Replaceable lens and bulb. Corrosion resistant steel housing. Recessed mount with built-in flange. 2-Wire design. (1) 1076 incandescent bulb included. Great Prices for the best trailer lights from Optronics. Optronics Back Up Light - Round - Clear Lens part number BU41CB can be ordered online at or call 1-636-306-4830 for expert service.
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  • Reviews (39)
  • Q & A (0)
  • Videos (1)
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Optronics Trailer Lights - BU41CB

  • Tail Lights
  • Round
  • Incandescent Light
  • White
  • 4-1/2 Inch Diameter
  • Recessed Mount
  • Backup
  • Non-Submersible Lights
  • Optronics

5-3/8" Round. Incandescent trailer light functions as a back-up light. Replaceable lens and bulb. Corrosion resistant steel housing. Recessed mount with built-in flange. 2-Wire design. (1) 1076 incandescent bulb included.


  • Round incandescent trailer light functions as a back-up light
  • Incandescent 1076 bulb is easy to replace
  • Snap-on acrylic lens
  • Steel housing resists corrosion
  • Recessed mount with built-in flange - hardware not included
  • 2-Wire design includes power lead and ground wire


  • Overall dimensions: 5-3/8" diameter x 1-9/16" deep
  • Distance between mounting holes (center on center): 4-1/4"
  • Bulb type: 1076 bulb
  • Power draw at 12.8V: 1.182 amps
  • 3-Year warranty

Optronics BU41 Series Flange Mount Back Up Light Diagram

Manufacturer Cross Reference
Light will work as an exact replacement for:
Peterson # M411C

BU41CB Optronics Back Up Icandescent Light - Round - Flange Mount - Clear Lens

Alternate part number: BU-41CB

California residents: click here

Video of Optronics Back Up Light - Round - Clear 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 - BU41CB Review

Today we'll be reviewing part number BU41CB. This is the 4 1/2 inch round, clear trailer backup light from Optronics. The round trailer light is going to function as a backup light. It's going to feature your clear acrylic lens with a strong, durable steel housing that's going to hold up well against the elements. It's going to feature a replaceable snap-on lens as well as a easy to replace bulb. This is a incandescent bulb system.

It is designed to be a flange mount with the three mount holes that are spaced equally on the flange. You can see those right there. It's going to feature a two-wire design, including the lead wire, and then the white wire is going to be your ground wire. If we take a overall measure of the diameter of the unit, including the housing it's going to give us a measurement of 5 3/8 of an inch. It's going to give us a depth of 1 9/16 of an inch. Those holes, center on center, are going to be separated by 4 1/4 inch, and again that's going to be equal spacing as far as center on center, the distance between the holes.

We're going to go ahead and hook this 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 need to go ahead and connect the ground wire, and then we're going to connect our reverse function. So you can see here it's going to send out a nice consistent signal. Pretty quick response time for an incandescent light. And that clear acrylic lens allows a lot of light to come through, again sending out a nice clear, consistent reverse light signal. That's going to do it for today's review of part number BU41CB.

This is the 4 1/2 inch round, clear trailer backup light from Optronics. .

Customer Reviews

Optronics Back Up Light - Round - Clear Lens - BU41CB

Average Customer Rating:  4.9 out of 5 stars   (39 Customer Reviews)

5-3/8" Round. Incandescent trailer light functions as a back-up light. Replaceable lens and bulb. Corrosion resistant steel housing. Recessed mount with built-in flange. 2-Wire design. (1) 1076 incandescent bulb included.


I had great experience with your Company. I placed an order it came in, package was short one gasket, I emailed your Company, Trever reacted immediately, and had the missing gasket sent out. I couldn't ask for anything better.


I often recommend Etrailer to people in my community of RV repair and Renewable Energy. I wish someone would do a video on how to replace hubs-wheels-bearings on older travel trailers with the Dayton-Dexter-Fayette Star wheels and include details on how to identify the axle and weight class. If you want to see what your products have been used on, heres an Example. I bet you never thought Etrailer would be the source for parts on a wind turbines pivot, shaft and furling parts!


Bought these to match the tail lights i already had, i like the style and quality of the lights so far. I have yet to wire them up but they are mounted and look good. From my experience i would buy again.


Seem like a great product, simple and strait forward installation. 4 stars is only because I don't yet how well they will withstand the test of time.


Good product, great price. Extra quick shipping. These are mounted in the tailgate of my Explorer with high power LEDs in them (one red one amber). I am a Fire Chaplain and respond to emergencies all over the county. These are part of my emergency light set up and do a great job. I did paint the fixtures with Gloss white automotive enamel and they blend right in to the tailgate. Etrailer has always given me good service with a good product at a good price. Hard to beat that combination.


Perfect fit to replace my existing sealed unit back up lights


The order was correct shipped quickly and was accurate. These are the original replacement appearing 4" back up lights for trailers. These fit my 39 foot fifth wheel perfectly!


exactly as advertised. Delivery quick.


Gents [and ladies] - I chose to purchase these lights from you due to your low cost. The quality of the fixture is perfect. Its single cast piece design makes it mostly water proof. Being flush mount keeps it from mechanical harm. I intend to use it camping and Ice fishing but I will replace the incandescent with an Led and a PWM ckt.

Thanx - Jeff.


This product was perfect for the repair we needed to do on our RV. Thanks!

Good product and easy to install.
Sandra - 04/25/2021


Great product, Great company. I will buy no where else when it comes to keeping my trailers up!


Product delivered quickly and exactly as described. I am installing them in a 6 wheel ATV project and they fit well. The price was right too! Will add pictures as soon as I finish the paint job.


Quality products, fast service, great prices, friendly people.
"Best of the Best"

Curt L


product was exactly what i had expected. should make great reverse lights for my jeep project and at a great price. customer service was on point as well.


cool product great design these will work great mounted in my toolbox for bed lights


etrailer was the only place that I could find this particular light with a clear lens. Very solid housing. Well made. Even comes with a rubber gasket. Thanks.


The backup lights were just what I was looking for. This was the only place I could find them. They arrived in just a few days and were in perfect condition.


thanks for your help in getting me the right backup lights.


Excellent fixture. Solid metal housing. I bought this light because of the replaceable lens and bulbs.


As described, good quality, great price, prompt shipping. Thanks


Replaced lights on RV. Lights worked perfect. The price was great and prompt delivery also


Exactly what I needed. Fast service


Exelent quality ships fast


Exact replacement


Quick delivery and perfect match to existing lights on front of my rv, definitely will use them again

Show More Reviews

See what our Experts say about this Optronics Trailer Lights

  • Availability of Reverse Light for 2010 Ranger Trailer
    I was able to find a picture of the light that you have on an old eBay listing. It looks like a surface mount reverse light that uses a 3 bolt flange. The closest thing we have to it would be the 4-1/2" Round Trailer Back Up Light # BU41CB but it might be a bit bigger. The light is 4-1/2 inch in diameter and the mounting flange is 5-3/8 inch in diameter. This could work for you as long as you are okay with potentially enlarging the hole on your trailer. I attached a review video for you...
    view full answer...
  • Size Hole Needed to Install 4-1/2" Round Trailer Back Up Light # BU41CB
    The hole size needed to install the 4-1/2" Round Trailer Back Up Light # BU41CB is 4-1/2 inches. The mounting flange diameter is 5-3/8 inch.
    view full answer...
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  • Interior Black Puck Light Recommendation
    I went ahead and checked to see if the Gustafson 12V RV Ceiling Light # 277-000483 is available in black, and it is only available in the satin nickel color. The closest light we carry that is similar to # 277-000483 and is black in color, is the Optronics Back Up Light # BU41CB. This light has a 2-wired deign, is recessed mounted, and measures 5-3/8" for an overall diameter, and is 1-9/16" thick. This light is designed to be used as a backup light, however it can be used inside your...
    view full answer...
  • How to Wire Reverse Lights on a Trailer with a 4-Way Trailer Connector
    Here's what you'll need to do. You'll need to get rid of the 4 pole on your trailer, and replace it with a 5 pole, part # HM47910. The extra lead on the plug would be extended using a length of 16 gauge wire # 16-1-1, sold by the foot. Split the wire off so it connects to the brown wire on each reverse light. Make sure the white ground lead for each lamp grounds to the trailer frame or to metal that's connected to the trailer frame. The fifth pin in your adapter will go hot when the vehicle...
    view full answer...
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Info for this part was:

Employee Mike L
Expert Research:
Mike L
Employee Jameson C
Expert Research:
Jameson C
Employee Cole B
Installed by:
Cole B
Employee Brian T
Updated by:
Brian T
Employee Matthew E
Updated by:
Matthew E

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