Adjustable Rebound and Compression damping Monotube Shock with External Piggyback Reservoir High Pressure Nitrogen Gas Charged STX Single Tube design 36 mm Piston Diameter Adjustable Preload w/ tool For Honda Grom rider over 80kg / 176lbs, **If under 80kg / 176lbs see HO 424 Top Level Comfort, Rideability and Performance Hard Anodized - Precision CNC-Machined Components Low-friction Shaft / Seal Head design Fully Serviceable and Repairable. SHOCK OHLINS HO 819