Arrives before Christmas 
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You're rewiring an old trailer and want to do it right. This 25-foot Y-harness lays in smooth, splitting left and right so you don't need jumper wires. Splice it in, test it, and you are ready to go.
This 4-pole Y-harness features a wishbone design that splits the wiring for easy routing down both sides of the trailer, eliminating the need for jumper wires. Full-length ground wire ensures consistent grounding for reliable trailer lights. The 25-foot length is ideal for longer trailers, providing ample reach to all lights without extensions. Color-coded wires simplify installation, and the plastic housing helps protect against moisture and grime.
California residents: click here
Videos are provided as a guide only. Refer to manufacturer installation instructions and specs for complete information.
Hi, everybody Andy here with etrailer.com. Let's take a real quick look at this Towsmart 4-Wire Y-Harness connector. Now this 4-pole Y-harness features a wishbone design that's going to split the wiring for easy routing down both sides of your trailer. That's going to eliminate the need for jumper wires. And this is altogether 25 foot long, so this is gonna be great for longer trailers giving you ample reach to all lights without extensions. The color-coded wires are gonna simplify installation, then the plastic housing's going to protect against moisture and grime.
But I think that's going to wrap up our real quick look today. I do hope that our brief time together was helpful for you, if you happen to have any other additional questions don't hesitate to reach back out to us we do wanna make sure that you're getting exactly what you want and need. We'll again, my name is Andy, thank you for joining me.
This product is exactly as advertised. Have rewired my trailer with no problems.
Plug that attaches to the car is garbage. I couldn't get the lights to work after rewiring it and putting in new tail lights so I rechecked everything, redid the ground to the fram, still didn't work. Looked at the connection and the plug wasn't seating on the car's plug. Trimmed the plastic around the ground connection down so it would seat - one side's lights now worked. Looked at the prongs on the wiring harness plug and they seemed too small for the car's receptecle. Took a punch and opened up the prongs, plugged it in and all of the lights now work. Going to have to solder the prongs so they stay large enough to maintain contact. What did I pay for - a bunch of wire? The cheap, crappy plug led to major frustration and extra work. I've been a fan of etrailer and expect to stay one but you only get so many of these.
Lazer S.
11/18/2025
I must admit to being surprised to hear that, Barbara. We have sold a pretty large number of these and this is the first time I have heard of there being an issue. Does the plug on your vehicle get a lot of use? And is it factory or aftermarket?
Fast shipping
Very nice perfect fit for my boat trailer thanks.
Exact copy of the original harness on a 17 year old trailer.
Exactly what we needed
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Lazer S.
9/16/2025
Glad to hear it, Kenneth! What kind of trailer did you rewire?