Genuine OEM Volkswagen Gas-Filled Hydraulic Shock Absorber, part number 12E513025A. This shock absorber is a critical component of the rear suspension system, responsible for controlling the spring's oscillations and absorbing road shocks. It is mounted to the vehicle's chassis and suspension arm. Filled with gas and hydraulic fluid, it provides consistent damping performance across a range of temperatures. Genuine OEM parts are calibrated for specific suspension geometry and weight, ensuring optimal ride comfort and vehicle stability.