Genuine OEM Audi Coolant Bypass Hose, part number 80A121081DH. This hose is an integral part of the engine cooling system, designed to route coolant around the thermostat under specific operating conditions. This function is crucial for efficient engine warm-up and temperature regulation. Weighing 0.068 kg, this hose assembly is engineered for precise routing and durability. Using a genuine OEM hose ensures proper fitment, resistance to high temperatures and pressures, and prevents leaks, which are vital for maintaining engine health.