Progressive Suspension claims these are the most adjustable shock in the V-Twin market. They feature complete adjustability with a 0.4” adjustable height eyelet, rebound damping adjustment, High & Low Speed compression damping adjustment via easily accessible knobs, and threaded hand adjustable spring preload. They also feature 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. The new and improved engineered jounce bumper features a captured design to help smooth and control bottoming. Shocks with spherical bearings in the mounting eyes prevent side-to-side movement from the swingarm being transferred throughout the rest of the chassis. Every shock is hand-built, tuned and dyno tested. Engineered for aggressive sport inspired riders, the 990 sets the mark for excellence on your V-Twin motorcycle.