Anytime Tools 10 piece DIAMOND DUST HOLE SAW DRILL BIT for TILE GLASS MARBLE ROCK Professional Qaulity Core Drill Bits Segmented design works better and lasts longer. 40 GRIT for use with stone and glass 10 Sizes included: 2-3/8", 2", 1-1/2", 1-3/8", 1-1/4", 1", 3/4", 1/2", 3/8", 1/4" Note: use on a low speed with coolant (water/oil)