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Peterson Trailer License Plate Light - Incandescent - Gray Housing - Clear Lens

Peterson Trailer License Plate Light - Incandescent - Gray Housing - Clear Lens

Item # M400
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M400 - Rectangle Peterson License Plate Lights
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2-11/16" x 1-1/2" x 2-1/8". Incandescent trailer light illuminates your trailer's license plate. Vibar socket absorbs road shock and vibration. Durable ABS housing. Surface mounts to trailer. 1-Wire design. (1) 168 bulb. Lowest Prices for the best trailer lights from Peterson. Peterson Trailer License Plate Light - Incandescent - Gray Housing - Clear Lens part number M400 can be ordered online at etrailer.com or call 800-298-8924 for expert service.
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Peterson Trailer Lights - M400

  • License Plate Lights
  • Rectangle
  • Incandescent Light
  • White
  • Surface Mount
  • 2-11/16L x 2-1/8W Inch
  • Peterson

2-11/16" x 1-1/2" x 2-1/8". Incandescent trailer light illuminates your trailer's license plate. Vibar socket absorbs road shock and vibration. Durable ABS housing. Surface mounts to trailer. 1-Wire design. (1) 168 bulb.


  • Compact light illuminates your trailer's license plate
  • Vibar socket absorbs road shock and vibration to prolong bulb life
  • Incandescent bulb can be easily replaced
  • Durable ABS housing and polycarbonate lens
  • Internal parts are constructed with stainless steel or tinned-brass to resist corrosion
  • Clear screw-on lens over incandescent bulb
  • Surface mount to trailer - hardware not included
  • Single wire design grounds through mounting hardware
  • DOT compliant when mounted above the license plate
  • Made in the USA


  • Dimensions: 2-11/16" wide x 2-1/8" thick x 1-1/2" tall
  • Distance between mounting holes (center on center): 1-3/4"
  • Bulb type: 168
  • Power draw at 12V: 0.35 amps
  • Limited 1-year warranty

Peterson 400 License Plate Light Dimensions

Surface-Mount Light

Surface-mount trailer lights install using a flange or bracket with mounting holes. These lights lay flat against the trailer surface and only require a small, often pre-existing hole, for wiring. Mounting hardware is used to secure the light to the trailer.

M400 Peterson Trailer License Plate Light - Incandescent - Gray Housing - Surface Mount - Clear Lens

Video of Peterson Trailer License Plate Light - Incandescent - Gray Housing - Clear Lens

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

Video Transcript for Review of Peterson Trailer Lights - Liscense Plate Lights - M400

Today we'll be taking a look at the Peterson trailer license plate light. This is going to help to illuminate your license plate on your trailer to help stay within compliance when it's mounted above that license plate.It's just a small incandescent bulb inside there. To replace that bulb, just need to back out the Phillips head screw up at the top, and then that'll just assemble the whole thing. It's really just held in place by that little guy. Then we can pull apart our housing. We'll see in there we'll have a vibe bar or V bar socket.

It's kind of like a rubbery material that holds that in place. That helps to absorb some of the road shock and vibration so it's going to help that foam to last a bit longer so you don't have to replace that out as quickly.This is also how you'll need to mount this base portion. You have to take this cover off to get the hardware in place. Now it doesn't come with any mounting hardware, so you will have to pick some up on your own, but you will have to take that cover off to get it installed. Of course, to put everything back together we just do the reverse.

Pop our cover back over. These two pieces might come apart on you. They just fit together pretty easily. The clear portion kind of fits inside that gray portion. There's a little tab on the inside that fits together.

Just want to get your little screw lined up with the metal portion inside. Tighten that back down. Doesn't have to be super tight, just enough to hold everything.It does just surface mount up to your trailer. Again, no hardware's included, but those two rivets are going to provide the ground connection to the trailer. That'll be what needs to make contact there so you get a good ground.

Then our single wire coming off the back is going to be our power.As far as measurements, the widest part of the base is about 2 and 3/4 inches, if I go to the outside edge of that rubber grommet at the back. If we go to the light housing it's a little bit more like 2 and 11/16. Then that's going to be about 1 and 5/8 inches tall, or again if we go to just the housing is about 1 and 1/2 inches. Front to back, it's about 2 and 1/4 inches long, about 2 and 1/8 if we don't count that little grommet on there. The distance between those mounting holes, center to center is about 1 and 3/4 inches. The diameter on those is about 3/16. The length of wire coming off of our light is about 6 inches, about 6 and 1/2 maybe.I'm going to hook this up to some power so you can get an idea of how bright it is. I'll put my power on that little black wire, and then ground will go to one of those rivets. Turn on the power source. That light comes on. It's not super bright, but it is there, help us illuminate that license plates. I'll go ahead and turn the lights out in the studio you can better idea how bright it is. If we put it above a license plate here, can you see it does illuminate it so we can still stay within compliance.The power draw at 12 volts is 0.35 amps. It does come with a one year warranty from Peterson, and it is made in the USA. That bulb type in there is a 168, which is pretty common. You can find that just about anywhere out there.That's going to do it for our look at the Peterson trailer license plate light.


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Info for this part was:

Video Edited:
Kathleen M
Edited by:
Daron K
Written by:
Brian T
Updated by:
Matthew E

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