This heavy-duty SPST relay harness is engineered for reliable performance in demanding automotive, marine, and industrial applications. Operating at 12V DC with a robust 40A rating, it features color-coded wires for foolproof installation and maintenance. The compact design incorporates premium silver alloy contacts that deliver exceptional switching reliability and a remarkable 100,000-operation electrical lifespan. With its low power consumption of just 1.8W and quick response times (15ms operate, 10ms release), this relay maximizes efficiency while maintaining high sensitivity. Built to withstand challenging conditions, it operates seamlessly across temperatures from -55°C to +70°C and features a sealed protective design. The relay's impressive specifications include a 1500VAC isolation between contact and coil, along with a contact resistance of ≤100MΩ. Perfect for trucks, vans, motorcycles, and boats, this versatile relay module provides the durability and performance needed for critical switching applications. Each unit comes with a pre-wired harness socket, making installation straightforward and secure.