The JD1912 Car Relay Harness is a reliable 12V 40A 4-pin SPST relay solution designed for a wide range of automotive applications, including cars, trucks, vans, and motorcycles. Built with heavy-duty 12AWG wiring, this relay harness is engineered to handle demanding DC switching tasks with ease. The pre-wired socket harness features color-labeled wires, making installation quick and straightforward without the need for specialized tools. The compact design measures approximately 0.98 x 1.06 x 1.10 inches, allowing it to fit comfortably in tight engine bays. The included metal mounting bracket (0.59 x 1.57 inches) ensures secure placement. Operating safely at low voltages below 50V AC or 75V DC, this relay is ideal for general-purpose switching needs. Each pack includes four complete harness sets, giving you multiple installations or convenient backup replacements. The color-coded wiring system minimizes the risk of incorrect connections, ensuring a safe and efficient setup every time.