Please Note : Communication is the best way to solve problems. If you have any problems after purchase, please contact us in time before opening the return . We will give you a satisfying solution. Fits the Following Vehicles: For Mercedes-Benz For 2012-2015 C250 For 2012-2015 SLK250 How a Car Thermostat Works: The thermostat controls the flow of coolant through the radiator. Mounted on the engine block, it adjusts the coolant flow to maintain the engine's optimal operating temperature by directing hot coolant towards the radiator when necessary. Q&A: 1. How to replace the thermostat? Removing the Old Thermostat .