The Gates Heavy Duty Engine Coolant Thermostat is designed to provide reliable valve response for smooth operation and accurate engine cooling. This thermostat features a quality controlled factory calibration that assures accuracy of opening and closing, regardless of pressure changes. It also features a temperature sensitive heat motor for reliable valve response. This thermostat is designed to fit, function and design are identical to OEM products. FleetPride is your First Click in Heavy Duty®.