Fox Suspension Float RP2 Boost Valve Rear Shock Boost Valve: Our patented Boost Valve technology provides a feeling of endless travel & plushness like that of a downhill rig, but with with XC pedaling efficiency. Weight: 0.5 lbs / 227 g (6.5" x 1.5" no reducers) Riding Style: XC, Trail, All-mountain. Adjustments: Rebound / Remote actuated Pro Pedal / Pro Pedal / Air spring pressure. Spring: Air. Buy Fox Suspension Float RP2 Boost Valve Rear Shock at Chain Reaction Cycles, the worlds largest online cycling store.