What Size Light Fits in a 4-1/2" Cutout?
Updated 08/15/2025 | Published 07/17/2025
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Question:
I am trying to replace the lights on a 2003 Lakota Colt horse trailer. Its a gooseneck 4 horse with tack room in the front. There are 4 markers down each side 3 amber 1 red, 2 round tail lights, and one light pod above the rear door. I have a question on ing the right size on the tail lights. These are round. The lens is 4 but the cutout in the trailer is 4-1/2. What size light do I buy? Im assuming 4 but want to make sure it wont be too small if it doesnt have a grommet large enough.
asked by: Andrew B
Expert Reply:
Hey Andrew, thanks for the information. For a 4-1/2" cutout you'll want a light with a 4-5/16" diameter like the item # STL43RB for Red or the item # STL43A24B for Amber. These will install with the Rubber Grommet for 4" Round Trailer Lights item # A45GB. That'll be a nice snug fit in your cutouts.
What size are your other lights? If you could get me dimensions or part numbers I can see if we have comparable replacement options.
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Product Page this Question was Asked From
Rubber Grommet for 4" Round Trailer Lights - PVC
- Accessories and Parts
- Trailer Lights
- Mounting Hardware
- 4 Inch Diameter
- Grommet
- Round
- Optronics
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Jerred H.
8/15/2025
Hey Andrew, how did the 4-5/16 diameter lights fit in your trailer's cutouts? I'm curious to know if they worked out well for you because it could help others with similar trailers.