Genuine OEM Audi Coolant Hose, part number 8W0121057. This hose is crucial for transferring coolant between various engine components, maintaining optimal operating temperature. It is located within the engine cooling system, connecting to the expansion tank and other hoses. Weighing 0.026 kg and measuring approximately 9.5 cm in length, this hose is engineered for precise fitment and durability. Using a genuine OEM hose ensures correct routing geometry and resistance to temperature and pressure fluctuations, preventing leaks and system failures.