Radiator Fan Thermostat Switch 85°c fits 30mm Hose Car Cooling Temp Control
So for example if your thermostat starts opening at 74°C you want an "on" temp of 84°C to 89°C so you would use the 85°C on switch. If your thermostat opens at 82°C you want an "on" temp of 92°C to 97°C so you would use the 95°C on switch.