PHYHOO 11pc Ball Sphere Diamond Burr Grinding Bits 0.6 to 6mm Fits Dremel Unique set of all-spherical grinding bits for Dremel-type rotary tools in durable storage case 11 ball sizes from 0.6mm to 6.0mm; 2.35mm-diameter shanks Each embedded with industrial diamond-grit for an incredibly-hard abrasive surface Diamond bits are favored for use with glass, tile, stone and hardened metals Excellent for carving, engraving, forming, drilling and filing/material removal