... stone(1). Diameter: from Ø3mm to Ø127mm(2). Shank/Top: Round, Trigonal, Hex (3). Diamond grit: D427, D252, D181 and cutting ... (6). Used to drill marble, ceramics, porcelain, tile, glass, fiberglass, quartz, bricks, and a variety of other materials. (7). It gives ... and use with or without center pin. Diamond core drill: round shank