Progressive 970 Piggyback Shocks For Harley Sportster Inspired by racers, riders and those that demand more of their bikes than weekend coffee runs, the 970 Series shocks combine a high pressure gas monotube design with deflective disc damping routed through two unique circuits and adjustable for compression damping via an easily accessible knob. Every shock is hand-built, tuned and dyno'd. Features: Progressive rate springs Threaded preload adjustments External compression adjustment knob allow for fine tuning to suit rider weight and riding style Lifetime warranty Built in the USA