Progressive suspension Fork Spring Kit Harley 49mm Dyna Softail Vrod FXD 2006^Progressive suspension Fork Spring Kit Harley 49mm Dyna Softail Vrod FXD 2006^ Heavy duty version of the Progressive Suspension fork springs The cost effective go to for a substantial increase in front end ride quality Includes Progressive Suspension rate springs combined with preload spacers Improves front end stability and brake dive control as well as increases comfort for heavier riders or those looking for a firm high performance feel out of