Genuine OEM Volkswagen Differential Housing, part number 0DF409021A. This housing encloses the differential gears, which allow wheels to rotate at different speeds during turns. It is a crucial part of the drivetrain assembly. The part weighs 5.645 kg and measures 0.17m x 0.17m x 0.13m. Genuine OEM differential housings are manufactured to exact specifications to maintain proper gear alignment and lubrication.