Wire Gauge for Optronics 25 ft. Wishbone 4-Way Trailer Wiring Harness

Updated 10/30/2025 | Published 02/18/2025

Question:

Gauge? Is it all AWG 16?

asked by: Brian D

Expert Reply:

Hi Brian; all of the wires used in the 25 ft. Wishbone 4-Way Trailer Wiring Harness # A25W42B are 20 gauge. If you have any other questions feel free to reach out in the comments below.

expert reply by: Robin H

Optronics Wishbone 4-Way Trailer Wiring Harness
(click to enlarge)

Robin H.

10/30/2025

Hey Brian, did the 20-gauge wiring on the 25 ft. wishbone harness end up working for your trailer setup? Knowing how it performed could help others choosing between wire sizes.

Brian J.

10/30/2025

@RobinH Dunno, didn't use it. I guess MAYBE AWG 20 is plenty, but since I'm no electrical engineer, I just went with a more standard 16 purchased as individual wires rather than the convenience of all-in-one four wiire strip. In fact, I could be wrong, but it seems to me that somewhere in eTrailer's FAQs you recommend something much more substantial than 20g for marker lights.