Milwaukee 2686-20 18V Cordless 4.5"/5" Grinder delivers 11,000RPM. Designed with paddle switch design, tool-free guard adjustment, overload protection and an electronic clutch. Quickly install and adjust guard with the tool-free guard adjustment. Grinder has an arbor size of 0.625. Grinder is lightweight at only 3.6lbs and is 12.25" long.