2 PCS Electric Fan Relay Kit, Dual Electric Fan Relay Kit, 185 Degree on 175 Thermostat Switch 40A Relays, 12V Cooling Radiator Fan Relays Wiring Kits for Replacing Faulty Wiring, Truck Engine Cooling....
Power coming into switch is + (red wire from power source). Load is power + coming out of switch to your project +. Ground is just that - (black wire) to your ground, and your project - wire connects to ground as well....
Not satisfied?. Color: Red....