Genuine OEM Volkswagen Engine Thermostat, part number 5QE121113. This crucial component precisely regulates the flow of coolant through the engine, ensuring it reaches and maintains its optimal operating temperature for peak performance and efficiency. It is vital for preventing both overheating and undercooling. Constructed primarily from durable plastic, it weighs approximately 0.187 kg. Choosing a genuine OEM thermostat guarantees the correct temperature calibration, reliable valve operation, and proper sealing for consistent engine thermal management.