Engineered to deliver performance unequaled by any other file, for use on ultrahard materials. Carbide, hardened steel, exotic metals, ceramics, and glass are no match for these precision files. Excellent material removal is the result of a unique process which bonds the 2-1/2 (64mm) long diamond surface. Available in fine grit, medium grit, and coarse grit. Overall length is 5-1/2 (14cm). 220 Grit Fine.