Put your cooler fan on autopilot with this Fan Thermostat (P/N 33-5721). No worries about cooking your engine because there are no more switches to remember to turn on or off. This Inline Thermostat attaches to the inlet port of the oil cooler or it can be spliced into existing 1/2" hose, and it activates at 180 degrees F. All fittings are 37 Degree.