This Is A Rough "n Tough Carbide Cutter (Coarse Ball) from Robart. Features: Made of virtually indestructable tungsten carbide bonded on steel shanks. Won"t wear out, load up, break down, or overheat. For use in shaping all woods, plastic, fiberglass and ceramics. Coarse grit. Ball shaped. INCLUDES: One Carbide Cutter (Coarse Ball) REQUIRES: Dremel High Speed Rotary Tool SPECS: Shank: 1/8" Diameter: 1/4" Comments: Not recommended for use on metal.RobartPart ROB462C