Replacement Trailer Taillight for ST-40 RS
Updated 02/17/2026 | Published 06/15/2024
Question:
looking for a pair of tail light assemblies ST-40 RS to retrofit to my A100 pick-up Diameter around 5
asked by: Richard V
0
Expert Reply:
Hey Richard, I did some digging and that part number looks to cross reference with the part # STL42RMB for an LED replacement. This is a recessed mount 4 inch diameter trailer taillight.
expert reply by:
Jameson C
0
Product Page this Question was Asked From
Optronics Trailer Light w/ Flange, Weathertight Plug - Brake, Tail, Turn - Submersible - Round - Red
- Trailer Lights
- Tail Lights
- Brake/Tail/Turn
- Round
- Recessed Mount
- Submersible Lights
- LED Light
- 4 Inch Diameter
- Red
- Optronics
more information >
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Jameson C.
2/17/2026
Hey Richard, how did the LED replacement tail lights work out on your A100 pickup? It’d be great to know if the 4-inch recessed mount gave you the fit you needed. Your update could make it easier for the next person with the same setup.