Genuine OEM Audi Transmission Ventilation Line, part number 0MJ301472A. This line is crucial for allowing air to circulate within the transmission system, preventing pressure buildup and ensuring proper fluid levels and operation. It is installed as part of the transmission assembly. As a flexible line, its precise routing and material integrity are vital. Opting for a genuine OEM ventilation line guarantees correct dimensions, material composition, and resistance to transmission fluids, which is essential for the long-term health and performance of the transmission.