Progressive Kvf300/400 512 Shock RR The 512 Series was the first aftermarket shock made specifically for Utility ATV's. They have undergone extensive R&D to provide the finest possible suspension for your workhorse vehicle. We use improved spring rates for heavier load stability and handling over rough terrain as well as increased length for more travel and ground clearance. The 512 Series comes with an adjustable spring preload to accommodate different loads (i.e. mounting a plow or carrying a hay bale). Also included is our Shock Sox to help keep dirt and mud out of the spring and to keep the adjusters clean. Features: 17.5 Length 2.15 - 3.00 Kg/Mm / 120 - 170 Lb/In Increase ground clearance and wheel travel 1-2 on most models Rugged double-steel-wall construction Progressive rate springs for comfortable ride and improved load-carrying capacity Five-position spring pre-load adjustment for varying loads Gas charged for fade-free operation Durable fabric Shock Sox are included to protect shocks from rock, sand and mud damage Shock Sox are easily removable with hook-and-loop fasteners for cleaning and adjustments Note : Not compatible with lift kits .