When your tow vehicle and trailer connectors don't speak the same language, the CURT 55510 wiring adapter closes the gap fast. Designed for common 4-pin flat wiring configurations found on trailers, campers, utility trailers, and tow vehicles, this compact adapter lets you make a solid electrical connection without splicing wires or running new harnesses. At just 0.67 lbs and a slim 9 x 4 x 3 inch footprint, it tucks away cleanly behind your hitch receiver or in a storage compartment when not in use.
Trailer lighting problems at the hitch are one of the most common delays before every tow. The CURT 55510 is purpose-built to solve mismatched or reversed 4-pin flat connector situations, giving you running lights, brake lights, and turn signals that work the first time -- without improvised fixes at the side of the road.
CURT is one of the most widely trusted names in towing accessories, and their wiring adapter lineup is built to the same standards as their hitches and brake controllers. The 55510 uses weather-resistant construction to stand up to road spray, humidity, and the general abuse of life behind a tow vehicle.
Measures just 9 x 4 x 3 inches and weighs 0.67 lbs -- easy to store in a tow vehicle glovebox, hitch bag, or truck toolbox.
Designed around the industry-standard 4-pin flat trailer connector, used on the vast majority of utility trailers, boat trailers, and light-duty camper trailers.
Plug-and-play adapter design means no wire cutting, crimping, or electrical tape. Connect and go.
Built to handle road spray, rain, and temperature swings typical of towing conditions across all seasons.
The 4-pin flat connector is the most common wiring standard for trailers rated under 3,500 lbs gross trailer weight. It carries four circuits:
This wiring standard does NOT carry a dedicated brake controller output or a 12V auxiliary power circuit. If your trailer requires electric brakes or a charge line, you will need a 5-pin, 6-pin, or 7-pin connector solution instead.
CURT's wiring adapter series covers a wide range of plug-and-socket conversions -- from 4-flat to 4-flat, 4-flat to 5-flat, 4-flat to 7-way round, and more. The 55510 specifically addresses 4-pin flat applications. If you are stepping up to a 5-pin or 7-pin round connector, see CURT's 5553x and 5756x adapter families.
The 4-pin flat connector carries no brake controller signal wire. If your trailer has electric brakes, you need a minimum 5-pin connector. Attempting to power trailer brakes through a 4-pin circuit will result in non-functional brakes -- a serious safety issue.
The CURT 55510 is a special order product through NTP distribution. Allow for additional lead time compared to standard stocked items. Confirm your connector style and trailer wiring type before ordering to ensure this is the correct adapter for your application.