Designed for use with U-Clip quick release shaft collars, Elasto-Ring Washer installs by hand and assures easy removal of U-Clip collar. When U-Clip is in place, Elasto-Ring is against spool flange — between flange and U-Clip. If back pressure starts to build, it is largely absorbed by Elasto-Ring which flexes against collar. Available in 10 sizes for shaft diameters from 8–35 mm, washer will not deteriorate from heat generated by friction coming from rotating spool flange.