This wishbone-style, 5-wire flat harness is great for a trailer with a surge coupler. The 40' long harness includes a 4' long ground wire and a blue auxiliary wire that signals your trailer brakes to disengage while you are in reverse.

This 18" long adapter plugs in to your 7-way, RV-style, vehicle-end connector to convert it for use with a 4-way or 5-way flat connector on your towed vehicle or trailer.

This adapter with coiled cord stretches 8' so you can connect your 7-way, RV-style, vehicle-end connector to a 4-way or 5-way flat connector on your towed vehicle or trailer.

The 5 way flat trailer connector is most commonly found on boat trailers that have hydraulic brakes. The fifth wire is hooked up to the reverse light circuit on the vehicle which then sends a signal to the hydraulic coupler to disengage the trailer brak es.