This Bilstein B4 OE Replacement 11-13 BMW X5 L6 3.0L/V8 4.4L Rear Right Twintube Strut Assembly is a high-end suspension product designed to provide superior ride comfort and handling performance. It features a monotube design with a gas-pressure construction to provide superior damping capacity and improved ride quality. The strut also features a zinc-plated finish for superior corrosion protection, and comes pre-assembled for easy installation. It is designed to be a direct replacement for the OE strut, and is backed by a limited lifetime warranty.