Genuine OEM Audi Coolant Hose, part number 8R0121055K. This vital component is responsible for transporting coolant within the engine cooling system, playing a critical role in maintaining optimal engine operating temperatures. It is positioned within the main cooling circuit, connecting key components like the radiator and engine block. Weighing approximately 0.234 kg and measuring 0.39 meters in length, this hose is engineered for specific routing and pressure resistance. Choosing a genuine OEM coolant hose ensures the correct material composition, precise internal diameter, and exact routing geometry for leak-free operation and efficient heat exchange.