The Bilstein 17-21 BMW 530i xDrive B4 OE Replacement Shock Absorber - Front Left is a high-performance, direct-fit suspension component designed to provide a smooth ride and superior handling. It is constructed from high-grade monotube gas pressure technology, which offers consistent damping performance and improved durability. This shock absorber is designed to be an exact OE replacement for the front left wheel of the BMW 530i xDrive model and is backed by a limited lifetime warranty.