This JD1912 automotive relay harness is engineered for reliable circuit control in vehicles and equipment. Operating on 12V DC with a robust 40A current capacity, this 4-pin SPST relay provides dependable switching for demanding automotive applications. The harness features color-coded wires for foolproof installation, while its sealed construction shields internal components from moisture and debris. Measuring 1.1 inches wide by 1 inch deep, with a 5.2-inch wire length, this compact relay is ideal for cars, trucks, vans, motorcycles, and boats. The mounting bracket ensures secure installation, while the standardized pin configuration maintains broad compatibility across various applications. Perfect for controlling auxiliary lights, fans, horns, or other vehicle accessories, this relay harness delivers professional-grade performance with straightforward installation.