Genuine OEM Volkswagen Fuel Tank, part number 3Q0201055BS. This fuel tank is designed to safely store the vehicle's gasoline supply. It is marked as number 1 in the diagram and features a narrow filler neck with a 22mm diameter, specifically for unleaded petrol. A properly functioning fuel tank is crucial for vehicle operation and safety, preventing leaks and ensuring a consistent fuel supply to the engine. Genuine OEM fuel tanks are constructed from durable materials and designed for a precise fit, maintaining the integrity of the fuel system.