30 Piece Diamond Coated Bur Set 1/8 - Inch Shank , 40 Grit Fits Rotary Tools 30 diamond coated burs 40 Grit Great for filing glass, ceramics, tile, brick, plastics, wood, fiberglass, stone, rock carbide, gold, platinum, silver, metals 1/8 in. (3 mm) shank.