Genuine OEM Audi Engine Cooling Hose, part number 4M0121081BK. This vital component is responsible for transporting coolant within the engine cooling system, specifically connecting the radiator to the expansion tank. It ensures proper circulation of coolant to maintain optimal engine operating temperatures. Weighing 0.102 kg and measuring 0.79 meters in length, this hose is engineered for precise routing and resistance to heat and pressure. Using a genuine OEM cooling hose guarantees the correct material composition, flexibility, and connection integrity, preventing leaks and ensuring long-term cooling system reliability.