Genuine OEM Audi Coolant Hose, part number 4H0121056K. This hose is an integral part of the engine cooling system, responsible for carrying coolant to regulate engine temperature and prevent overheating. It is positioned within the cooling circuit, connecting key components like the radiator. Made from durable, heat-resistant rubber, it weighs approximately 0.26 kg. Choosing a genuine OEM coolant hose ensures the precise routing geometry and material integrity required for reliable, leak-free performance under engine operating conditions.