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Adhesive Reflector for Truck or Trailer - 3-3/16" Round - Stick On - Red - Qty 1

Adhesive Reflector for Truck or Trailer - 3-3/16" Round - Stick On - Red - Qty 1

Item # RE21RB
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3-3/16" Diameter red trailer reflector enhances visibility on the road. Durable acrylic construction. Surface mounts with adhesive backing. Meets FMVSS requirements. Lowest Prices for the best trailer lights from Optronics. Adhesive Reflector for Truck or Trailer - 3-3/16" Round - Stick On - Red - Qty 1 part number RE21RB can be ordered online at or call 1-800-940-8924 for expert service.
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  • Reviews (3)
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  • Videos (2)
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  • Why etrailer?

Optronics Trailer Lights - RE21RB

  • Reflectors
  • Round
  • Red
  • 3 Inch Diameter
  • Surface Mount
  • Optronics

3-3/16" Diameter red trailer reflector enhances visibility on the road. Durable acrylic construction. Surface mounts with adhesive backing. Meets FMVSS requirements.


  • Round red trailer reflector enhances visibility on the road
  • Durable acrylic construction
  • Surface mounts with adhesive backing
  • Meets FMVSS "A" when properly applied


  • Dimensions: 3-3/16" diameter
  • Quantity: 1 reflector
  • 3-Year warranty

dimensions of reflector

Manufacturer Cross Reference
Reflector will work as an exact replacement for:
Uni Bond # RF3001R
Truck Lite # 98005R3
Grote # 40052
Peterson # B475R

Manufacturer Specifications

RE21RB Optronics Self Adhesive Round Trailer Reflector - 3" Round - Qty 1

Alternate part number: RE-21RB

California residents: click here

Video of Adhesive Reflector for Truck or Trailer - 3-3/16" Round - Stick On - Red - Qty 1

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

Video Transcript for Optronics Round Trailer Reflector Review and Installation

Hey everybody Ryan here at etrailer, today we're gonna be checking out the Optronics Round Trailer Reflector. So, when it comes to making your trailer a little more visible, can never really go wrong with that. You know, especially today, you got a lot of distracted drivers. And so by adding some reflectors it's a quick way to, throw off some light and, and let people be able to see your trailer a little bit easier. Nice thing with the reflectors is, you don't have to wire them off or anything like that. Once you get 'em on there and you're kinda done with them and they're gonna do their job.

Especially with these, they just stick on. So, super simple, anyone can put 'em on and make you that much more safe. So, something that's pretty cool with these is, they're pretty generic. Chances are pretty good they're gonna work just about anywhere on your trailer. One thing to pay attention to though is a lot of times if you try to put it on the side, you know on a smaller trailer like this, this may overhang a little bit, and to figure that out exactly the overall diameter of the reflector is gonna be 3-3/16 of an inch.

So just kinda as a reference or an image. You know it's about the same size as a hockey puck. Now with that said, you know you can really just slap these things anywhere and go. With this one being red, you typically want these to face towards the back of the trailer. But for your sides and anything facing towards the front, there's also Amber colored reflectors available as well.

So like any reflector, you wanna see if it actually works or does a good job, and when I had turned off the overhead lights, grabbed my flashlight to simulate the vehicle's headlights. And as soon as that light starts to hit it, it illuminates it. It gets pretty bright. Whether the lights indirect, or spot on, when it's spot on it, it really does a great job, it gets super bright. And so, you know, it's gonna do exactly what it's supposed to do.

And do a great job at it. So to get the light put on, really not a whole lot to it, it's really all just in the prep work since it's just a two sided sticky tape. So, find a spot where you wanna put it, whether you're adding it or replacing an old one. So I think we're going to put this one right here on the fender. And really the only thing you gotta look out for is to make sure that surface is nice and clean. So I got some rubbing alcohol and a rag here. Give that a good wipe to make sure it's all clean, that way our sticky tape will get proper adhesion. If your trailer's really rusty or something like that, probably wouldn't be a bad idea to kinda sand it down, make it smooth, maybe put a fresh layer of paint over it. But, regardless on what you do, you wanna make sure that it's clean and dry. Once we're all dry, you just peel that backing paper off. Place it where you want it. And simply just push it into position. So at the end of the day, really simple and inexpensive way to help keep you a little more safe..

Customer Reviews

Adhesive Reflector for Truck or Trailer - 3-3/16" Round - Stick On - Red - Qty 1 - RE21RB

Average Customer Rating:  5.0 out of 5 stars   (3 Customer Reviews)

3-3/16" Diameter red trailer reflector enhances visibility on the road. Durable acrylic construction. Surface mounts with adhesive backing. Meets FMVSS requirements.


Just what I was looking for! We needed inexpensive reflectors for our mail boxes and culverts. The package shipped before promised and the reflectors were delivered before I expected them.

Reflectors with one mounting hole in center require less hardware and hold up better than ones with plastic end tabs. We are rural with no street lights, and these reflectors really help us negotiate our road.
Dan l - 09/20/2015


Excellent equipment!



Ask the Experts about this Optronics Trailer Lights

  • Replacement Red Reflector for Reese Hitch Bike Carrier 63123
    We do not carry an exact replacement red reflector for the Reese hitch bike rack # 63123 but we do have a handy self-adhesive reflector that measures 2-3/16-inches in diameter, part # RE37RB. We also offer a larger 3-3/16-inch reflector, part # RE21RB, which is also self-stick. Since there is no visible retaining screw for the reflector on the rack, chances are it too is a self-stick type.
    view full answer...
  • Difference of Reflectors Available
    There's not a lot of difference in reflectors. One thing to think of when choosing one is how to mount it. Some, like # RE13RB, mount by screwing on. Others, like # RE21RB, mount with adhesive. Anything labeled DOT isn't necessarily a better or worse product. It just means that it's approved for use by the Department of Transportation. Which means that when used for its intended purpose it will be legal on the roads.
    view full answer...
  • How To Add Reflectors to the Mount-n-Lock Heavy-Haul'r RV Bumper Replacement Kit
    If you want to add reflectors to the Mount-n-Lock Heavy-Haul'r RV Bumper Replacement Kit part # MNT74FR I'd simply use the Adhesive Reflector for Truck or Trailer part # RE21RB. These feature a stick-on install so you don't have to worry about drilling and dealing with galvanic corrosion due to the bumper's aluminum construction.
    view full answer...

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Info for this part was:

Employee Joshua S
Video by:
Joshua S
Employee Jacob T
Video Edited:
Jacob T
Employee Laura H
Updated by:
Laura H
Employee Brian T
Updated by:
Brian T
Employee Noah M
Updated by:
Noah M
Employee Cole B
Installed by:
Cole B
Employee Ryan G
Installed by:
Ryan G

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