Genuine OEM Audi Fuel System Vent Hose, part number 4G0201991L. This hose is an integral part of the fuel system, designed to safely vent gases or fuel vapors from various components, such as the fuel rail or associated lines. It plays a role in maintaining optimal system pressure and preventing vapor lock. The hose is located within the fuel line assembly. Weighing approximately 0.12 kg and measuring 0.49 meters in length, it is constructed from materials resistant to fuel and its vapors. Genuine OEM hoses ensure the correct routing, material integrity, and secure connections for safe and efficient fuel system operation.