HOTSYSTEM Car Truck 12V-A 12V Volt DC 40 A Relay & Socket SPST 4Pin 4 Wire Interlocking relay sockets Heavy-duty impact molded relay socket with 4 WIRES,17AWG High 40A coil capacity- able to handle those high current applications with ease Hundreds of uses include- starter kills, domelight supervision, trunk release, polarity change,power door lock/actuator control, change a low current output to high current,add ignition/accessory outputs, control motors/other electronics, It is Also suitable for automobile used for control, alarms, horn, headlight and more