Genuine OEM Audi Gear Detection Sensor O-Ring, part number WHT008644. This vital sealing component is located around the gear detection sensor in the transmission assembly. Its function is to prevent transmission fluid leaks and protect the sensor from contaminants, ensuring accurate gear position readings. Genuine OEM O-rings are manufactured from specific materials to withstand transmission fluid and temperature extremes, providing a reliable and durable seal essential for transmission longevity.