A 7-way connector (or 7-pin connector) is a heavy-duty electrical plug used to connect a towing vehicle to a trailer, RV, or camper. Unlike simpler 4-way connectors, the 7-way supports advanced functions like electric trailer brakes, brake controller signals, reverse lights, and auxiliary 12V power to charge the trailer battery. It is the industry standard for large trailers, goosenecks, and 5th wheels.