Genuine OEM Audi Emission Vacuum Check Valve, part number 078611933C. This compact plastic valve is designed to precisely control the flow of vacuum within the vehicle's emission system, ensuring efficient operation and compliance with emission standards. Weighing 0.01 kg, it is a small but vital component. Choosing a genuine OEM check valve guarantees correct pressure thresholds, reliable one-way flow, and seamless integration with the complex emission control system.