Genuine OEM Audi fuel tank vent line, part number 420201167B. This line is a critical component of the fuel system, facilitating the venting of fuel vapors to maintain proper pressure within the tank. It is marked as number 25 in the provided assembly diagram. Constructed to meet strict automotive standards, this vent line ensures durability and resistance to fuel vapors. Genuine OEM parts are essential for this application to ensure correct routing geometry and secure connections, which are vital for emissions compliance and overall fuel system safety.