Genuine OEM Audi Coolant Hose, part number 8R0121036A. This vital hose is responsible for transporting engine coolant, playing a crucial role in maintaining optimal engine operating temperature. It connects to the coolant expansion tank and other components within the engine cooling system. The hose features a quick-release coupling for secure and efficient installation and removal. Using genuine OEM coolant hoses ensures the correct routing geometry, material composition, and pressure resistance for reliable, leak-free performance under varying engine conditions.