Multifunctional Cutter Bit: High speed cutters can be used for carving, engraving, shaping, hollowing, grooving, slotting and making tapered holes in a variety of materials Strong: These grooving cutters are made of high-grade steel for more durability Versatile: Work well on various materials such as plastic, soft metal, concrete, brick, plexiglass, leather and woods including soft wood, hard wood, laminates, plywood and more Working diameter 4.8 mm; shank diameter 3.2 mm; recommended maximum speed 30,000 RPM Fits with all Dremel Multi-/Rotary tools or other 3,2mm shank size multi- / rotary tools