On Some vehicles the factory cooling fan is not triggered until well over 200 degrees F. This Robs your engine of performance and the tendency to pre-detonate is much greater. This switch will help lower your engine operating temperature by triggering the factory fan at lower coolant temperature. This item not legal for sale or use on California Pollution controlled motor vehicles. Price does not include shipping, call or email for a shipping quote. -200-185 Degree F Switch