AFCO Leaf Spring Sliders can eliminate the up and down movement of the rear springs eye caused by shackles moving though their arcs during suspension travel. Unloading points displace less during suspension movement. This makes for more consistent spring rates than when the shackle system is used. Sliders are more rigid than a shackle, lessening the chance of lateral binding. Sliders improve consistency and predictability of leaf spring equipped race cars.