Genuine OEM Audi Engine Coolant Return Pipe, part number 05A121491A. This pipe is crucial for directing coolant back to the engine cooling system, maintaining optimal operating temperatures. It is positioned on the left side of the engine assembly. Weighing approximately 0.115 kg and measuring 0.51 meters in length, it is designed for precise fitment. Choosing a genuine OEM coolant pipe ensures correct routing geometry, material integrity, and resistance to thermal cycling, preventing leaks and maintaining system pressure.