The Bilstein B8 Performance Plus shock absorber is a performance upgrade for OE dampers designed to be paired with after-market lowering springs. These dampers offer application-specific valve settings with a monotube design to bring out the best handling performance of a vehicle. This product represents a single rear shock absorber featuring a 46mm piston diameter. Package Contents: 1x Rear Shock Absorber (Part Number: 24-158756). Key features include: Monotube gas pressure technology, instant superior handling, and increased safety. Specifically tuned for vehicles with factory sport suspensions or lowering springs.