Progressive 990 Sport Shocks For Harley Dyna Progressive Suspension's 990 Sport Series shocks features complete adjustability with an adjustable height eyelet, rebound damping adjustment, High & Low Speed compression damping adjustment via easily accessible knobs, and threaded hand adjustable spring preload. The 990 features a high-pressure monotube with deflective disc damping routed through two unique circuits delivering a consistent feel through the damper stroke for improved performance and stability. Progressive's new and improved engineered jounce bumper features a captured design to help smooth and control bottoming. Every shock is hand-built, tuned and dyno tested in their facility and backed with a lifetime warranty. Engineered for aggressive sport inspired riders, the 990 sets the mark for excellence on your V-Twin motorcycle! Features: Adjustable Height Eyelet - 0.4 Adjustable Rebound Damping Adjustable Preload by Hand Adjustable High & Low Speed Compression Mounts using bearings High Pressure Gas Monotube Deflective Disc Damping Lightweight Aluminum Body Linear Rate Coil Spring Captured Jounce Bumper Lifetime Limited Warranty Notes: Depending on model, your stock shock length is 12 to 12.5 Shock lengths are measured fully extended, eyelet to eyelet on centers A change in height at one end of the bike may require a change at the other Changing ride height can potentially change the trail and mechanical trail Prior to purchasing shocks that are different than your OEM length, please verify that wheel and suspension travel can be altered without causing clearance issues to the swingarm, axle, frame, tire, fender, chain/belt and guard, and exhaust