Genuine OEM Audi Purge Valve, part number 420906321. This critical component regulates the flow of fuel vapors from the charcoal canister into the engine's intake manifold, preventing harmful emissions and ensuring efficient fuel system operation. It is a small, lightweight component weighing 0.145 kg. Choosing a genuine OEM purge valve ensures precise calibration for accurate vapor control, proper sealing, and reliable long-term performance within the complex emissions system.