Progressive Suspension® has unveiled another breakthrough design called Frequency Sensing Technology (FST) for its unique ability to dynamically adjust damping as you ride. This lowered stance makes it easier to manage your bike at intersections and parking lots| not to mention just swinging your leg over the seat. 944 ULTRA-TOURING: Specifically designed to deliver a comfortable ride at a 1" lowered stance; built around our latest FST technology| The Ultra Touring shocks utilize all the suspension travel provided by the full length units| but in a 1" lowered ride height (sits at stock height on FLHX| FLHXS| FLTRXS| FLHTKL| FLHTCUL); the unique Ultra-Touring spring combination not only delivers a lowered ride height while its being ridden| but also while itÂ’s on the side stand. 944 ULTRA-LOW: Just like the name implies| this is the lowest version of our 944 Series shocks; designed to sit 2" lower than a stock HD Touring model (1" lower on FLHX| FLHXS| FLTRXS| FLHTKL| FLHTCUL) and provide the best ride a short shock can; the 944 Ultra-Low is the shock for the job.