175 185 degree electric fan thermostat relay switch kit for your cooling system. 12V 40 Amp 4 Pin Relay & Pigtail, 3/8 inch and 1/2 inch pipe Includes everything you need to hook up to your fan unit: relay switch, circuit breaker, terminals, wires and mounting screws Key features Function: thermostat controlled relay switch kit to automatically operate your cooling fan based on temperature Voltage and current: 12V system; 40 Amp capacity; 4 Pin Relay and Pigtail Temperature trigger: activates at 175 185 degrees to protect against overheating Pipe compatibility: supports 3/8 inch and 1/2 inch pipe connections What's included 12V 40 Amp 4 Pin Relay & Pigtail Relay switch Circuit breaker Terminals Wires Mounting screws All components to connect to your fan unit Benefits Improves cooling efficiency by turning the fan on only when needed Helps prevent engine or equipment overheating Straightforward installation with complete, ready to use kit Compatible applications and use scenarios Automotive cooling systems: retrofit or upgrade radiator cooling with automatic fan control in 12V vehicles Marine and outdoor engines: manage engine cooling for boats or other 12V powered setups Generators and small industrial equipment: maintain safe operating temperatures with automatic fan activation This kit provides a complete and reliable solution for automatic fan control in 12V cooling systems, with a clear temperature range, standard pipe sizes, and all required hardware for installation.