Genuine OEM Volkswagen Fuel Tank Cap, part number 1K0201550AJ. This cap is designed to securely seal the fuel tank filler neck, preventing fuel evaporation, protecting against contaminants, and maintaining proper fuel system pressure. It is positioned at the vehicle's fuel filler opening. Weighing approximately 0.073 kg, this cap is made from durable, fuel-resistant plastic. Choosing a genuine OEM fuel cap ensures a precise fit, proper sealing, and correct pressure relief valve operation, which is crucial for emissions control and fuel system integrity.