Bilstein B8 5100 shock absorbers are designed as a direct fit solution for lifted trucks and SUV’s. These shock absorbers feature a monotube design which provides consistent fade free performance. B8 5100 shock absorbers utilize a unique, velocity sensitive, digressive piston which reacts to changing road conditions. All B8 5100 shock absorbers are tuned for each specific application to assure optimal performance is achieved. B8 5100 shock absorbers offer a significant improvement in ride quality, handling, and comfort.Torsion key is not included.