ICON’s 2.5 Aluminum Series shocks are designed and built to give your vehicle outstanding performance off-road and a smooth ride on the street. These shocks are configured specifically for each application in both length and damping tune. Featuring one-piece impact extruded aluminum cylinders these 2.5 Aluminum Series shocks offer lighter weight improved corrosion resistance and a more uniform finish than traditional plated steel cylinders. Like all ICON'S Shock Absorbers 2.5 Aliminum Series shocks are 100% rebuildable and 100% revalveable. For piggyback and specific remote reservoir applications ICON'S unique use of a 6061 billet aluminum manifold a few inches below the top cap of the shock creates an internal Bump Zone that when used creates an additional 20% of damping force. This additional force helps prevent harsh bottom outs and controls the suspension when compressing at high velocity. If you are looking for a more user defined tune consider looking into the Compression Damping Control Valve (CDCV) shocks.