American Volt 180'F Electric Radiator Fan Thermostat Sensor Ground Switch 1/8" Inch NPT Thread 180'F automotive engine grounding fan switch. 1/8" NPT brass thread-in temperature probe. Activates fan at 180 degrees and turns off at 165 degrees. Universal fit for any application with a 1/8" NPT port. Threads into engine block, radiator, manifold or water outlet.