The Charger 3.1 RC2 Piston Kit upgrades existing Charger 3 dampers to the NEW Charger 3.1. With increased damping range, Charger 3.1 RC2 is primed to take on any trail. Less compression damping in the Low Speed Compression open position and additional support in the High Speed Compression closed position gives you the traction, control, and comfort you need to charge dicey lines all day.