Fits ONLY 97 up 6.5 and ALL with dual thermostat configuration upgrade. Listing is for 1 thermostat. 2 required per application. All 330 series stats now include the rubber oring.There is no additional gasket used. “Thermostat temperature selection is more a matter of personal preference. I personally prefer the 190° stats, but the majority use the 180° stat.” – JK
