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Running new trailer wiring can be a pain, but this harness keeps things simple. The Curt T-Connector plugs in behind the tail lights using factory connectors, so there’s no cutting or splicing. Just match the plugs, route the 4-flat to the bumper, and you’re ready to tow.
Once installed, the 4-pole flat connector gives you the basics – running lights, brake lights, and turn signals. It’s the same standard connector most small and mid-size trailers use, so it’s easy to hook up and know everything’s working right.
The built-in converter keeps the vehicle wiring safe by managing how the trailer’s lights draw power. It isolates the trailer circuits so you don’t overload or backfeed your vehicle’s lighting system. That means steady, clean signals for your trailer every time.
If you ever need to tow something with a 5-way or 7-way plug, this 4-flat is a solid starting point. You can attach simple adapters like part #20036 or use a kit such as #ETBC7 to add full brake and charge lines later. It’s a straightforward way to grow your towing setup without redoing your wiring.

Customer Satisfaction Score:
96% were satisfied with this product
4% of customers were not satisfied
Ratings & Reviews

Gary L.
10/21/2017
its still working great. No issues at all

Scott
1/3/2022
This product failed and it was a pain in the ass to get it all worked out as far as the warranty thing goes … understandable since people scam all the time but man , I wasn’t too happy about the process . The new one works fine and has worked fine and I will for sure be getting a backup unit so if it fails while I’m on the road I’m not stranded because of an easy to fix plug and play part . It was easy to install for me … it seems to be working great at this point and I take my trailer for a drive a few times a month to keep it all working .

Jose
10/12/2025
Its a really awesome product it was very easy to install and it works great

John G.
4/3/2015
Excellent. Moved from Georgia to SC with truck pulling UHaul. Did Great!
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Kenneth
6/12/2025
Still functioning as it should.