Female-end connector socket that splices into your tow vehicle's own wiring, giving you a standard 4-way flat plug to connect any trailer's 2-wire lighting system.
Like trailer hitches and ball mounts, electrical connectors range all over the board in shape, size, and capability, but no matter what your trailer's electrical functions are, you need a solid connection to keep the power flowing. The Curt 58040 splices directly into your vehicle's own wiring, providing a standard 4-way flat socket for connecting a trailer plug.
This connector supplies power for tail lights, turn signals, and brake lights, plus a dedicated ground connection. Built with durable rubber-molded construction and 60 inches of color-coded, bonded 16-gauge wire, it's designed for straightforward splicing into 2-wire vehicle electrical systems.
Female end splices into your vehicle's wiring
Color-coded, bonded 16-gauge for easy splicing
Durable build for long-term outdoor use
Fits vehicles with standard 2-wire electrical setups
This is the vehicle-side (car end) female connector socket, designed to splice into your tow vehicle's wiring — it is not a trailer-side plug. It's meant to give your vehicle a 4-way flat socket to receive a trailer's plug, not to be mounted on the trailer itself. California Prop 65 Notice: This product contains a chemical known to the State of California to cause cancer and birth defects or other reproductive harm.
In The Package: • Vehicle-Side 4-Pin Flat Connector Socket with 60" Wires