... bits for various types of stone Electro-plated diamond core drill bit (hole saw) :-Fast, clean and efficient ... (2). Shank/Top: Round, Trigonal, Hex (3). Diamond grit: D427, D252, D181 and cutting thickness upon coating ... bag; Blister; or as your requirement (6). Used to drill marble, ceramics, porcelain, tile, glass, fiberglass, quartz, ... use with or without center pin. Drill: Diamond core drill bit