The Bilstein B4 Series 21-030512 is a high-quality gas-pressure replacement shock absorber designed to restore your vehicle's original handling performance and safety. Engineered as a Twintube Strut Insert, it provides the same damping characteristics as the factory-installed unit. Key features include constant damping power under any load, high traction, and precise handling. Designed specifically for the BMW E28 and E24 chassis. Package Contents: 1x Front Strut Insert (Art: 21-030512), 1x Mounting Nut, 1x Top Nut. Note: It is recommended to replace shock absorbers in pairs.