Genuine OEM Audi Coolant Hose, part number 1C0122051M. This hose is a critical component of the engine cooling system, designed to carry coolant to regulate engine temperature. It typically connects to the radiator, facilitating the flow of heated coolant away from the engine. Using a genuine OEM hose ensures the correct routing geometry, material composition, and resistance to temperature and pressure fluctuations for reliable, leak-free operation.