Genuine OEM Audi Cooler Line, part number 80A121081E. This line is responsible for transporting coolant within the engine cooling system to maintain proper operating temperatures. It is positioned on the front left side of the cooling assembly, connecting to the expansion tank. This lightweight component weighs approximately 0.03 kg. Choosing a genuine OEM cooler line ensures precise routing, secure connections, and resistance to thermal and chemical stresses for reliable cooling system function.