Progressive's 944 Ultra Low: Just like the name implies, this is the lowest version of the 944 Series shocks. Designed to sit 2" lower than a stock HD Touring model and 1" lower than stock Street Glide models and provide the best ride a short shock can! Frequency Sensing Technology (FST) allows the shocks to sense the frequency of a bump and automatically adjust damping for superior ride quality Adjust spring pre-load by hand, no special tool needed Progressive Rate Main springs specifically designed for touring Available in Standard or Heavy Duty