Genuine OEM Audi Power Steering Reservoir, part number 8E0422371B. This plastic container is designed to hold the power steering fluid, which is essential for the proper functioning of the hydraulic power steering system. It weighs approximately 0.2 kg and features specific inlet and outlet ports for fluid circulation. Using a genuine OEM power steering reservoir ensures correct fluid capacity, proper venting, and resistance to fluid degradation, maintaining consistent steering feel and system longevity.