Genuine OEM Volkswagen Transmission Breather, part number 0C8301047B. This component is designed to equalize internal pressure within the transmission, allowing air to enter and exit as temperatures fluctuate. It prevents pressure buildup that could damage seals and gaskets, ensuring proper lubrication and operation of the transmission. The breather is typically located on the exterior of the transmission housing. Using a genuine OEM breather ensures correct pressure regulation and long-term durability for the transmission.