The Bilstein 11-16 BMW 528i B4 OE Replacement Shock Absorber - Rear is a high-performance shock absorber designed to replace the original equipment shock absorber on the 11-16 BMW 528i. This shock absorber features a monotube design with a gas-pressurized piston and a self-adjusting deflective disc valve. It is designed to provide superior handling, stability, and control while also improving the ride quality. The high-quality construction ensures long-lasting performance and reliability.