M Series - Suspension Shock AbsorberBilstein M Series shock absorbers feature a steel monotube body with a 36mm piston designed for motorsports applications. These shock absorbers are available in 8 inch stroke with multiple valve setting options that provide optimal weight transfer and feel. They can also be converted to a coilover design (kit sold separately) for multiple platforms on dirt and asphalt. M Series shock absorbers are ideal for racers needing a lightweight high