Genuine OEM Audi Engine Cooling Thermostat Housing, part number 079121115BL. This component is a crucial part of the engine's cooling system, housing the thermostat that regulates the flow of coolant to maintain optimal engine operating temperature. Proper temperature control is vital for engine efficiency, performance, and longevity. Made from durable plastic, this assembly weighs approximately 0.48 kg. Choosing a genuine OEM thermostat housing ensures precise fitment, correct material resistance to coolant, and accurate thermostat function, preventing issues like engine overheating or undercooling.