Automatically adjust the water yield flowing into the radiator according to the temperature of the cooling water, so as to ensure that the engine works within the appropriate temperature range. Keeping your engine running smoothly to meet the harsh conditions of automotive cooling system, providing long-lasting durability. For Land For Rover For Range For Rover. The engine coolant thermostat is designed to regulate the cooling capacity of the cooling system to ensure that the engine runs within the appropriate temperature range. Withstands the demands of your vehicle's cooling system for lasting performance.