Progressive Suspension 12 Series Ps30 Dual Shocks BMW / Ducati / Honda / Kawasaki / Suzuki / Yamaha 12 series shocks are gas-charged for superior, fade-free damping and consistent operation. Features: Six-stage, automatic damping - designed with a special anti-topping function Double-wall shock body construction for piston protection and long life Shocks have black finish Springs sold separately Gas charged damping method