Genuine OEM Audi Coolant Hose with Coupling, part number 7L8121157D. This hose is designed to connect various components within the engine's coolant system, facilitating the flow of coolant and maintaining proper operating temperatures. It connects to the expansion tank and other hoses in the cooling circuit. Weighing approximately 0.12 kg and measuring 0.134 meters in length, it is a precisely molded component. Choosing a genuine OEM coolant hose ensures the correct material composition, pressure resistance, and exact routing geometry, which are essential for preventing leaks and ensuring reliable engine cooling.