5-Piece Heavy Duty Diamond Dust Hole Saw,3/4", 1", 1-3/16", 1-3/8", 1-5/8" Sizes: 3/4", 1", 1-3/16", 1-3/8", 1-5/8" To prolong the life of these bits, use on a low speed with coolant (water/oil) The diamond coating on these saws give superior performance and life Excellent results in granite, ceramic, porcelain, glass, marble, slate, and tile.