This rotary handpiece provides 320,000 RPM for effortless engraving, decorating, and grinding on almost any material. It only accepts 1.6mm diameter burs with FG shanks. Connects directly to a GraverMach® AT, GraverMax® G8, or any regulated air supply. The GRS® Ultra 850 High Speed Handpiece uses external compressed air (min. 2 – 2.5 bar, 38 l/min.).