Genuine OEM Audi Coolant Hose, part number 4M0121081DB. This hose is an essential part of the engine cooling system, responsible for circulating coolant between the radiator, expansion tank, and other engine components. It ensures efficient heat dissipation and maintains optimal engine operating temperature. Weighing approximately 0.0545 kg and measuring 0.52 meters in length, it is designed for specific routing and pressure. Choosing genuine OEM coolant hoses guarantees correct material composition for heat and pressure resistance, preventing leaks and ensuring long-term cooling system integrity.