Genuine OEM Volkswagen Differential Housing, part number 0AJ409021D. This is the main casing for the differential assembly, providing structural support and protection for the internal gears and bearings. Proper housing integrity is essential for maintaining correct gear alignment and smooth operation of the drivetrain. Manufactured to precise tolerances to ensure a perfect fit and seal. Genuine OEM parts guarantee the exact material composition and structural integrity required for safe and reliable drivetrain function.