Genuine OEM Volkswagen Exhaust Recirculation Valve, part number 038131501AQ. This valve is a key component of the exhaust gas recirculation (EGR) system, designed to control the flow of exhaust gases back into the intake manifold to reduce NOx emissions. It is marked as number 1 in the diagram. Genuine OEM EGR valves are precisely calibrated to ensure optimal engine performance and emissions compliance.