Professional grade Diamond Grill Hole Saws are for cutting hard to cut materials. Ideal for floor tile, wall tile, porcelain, glass, slate, marble, granite, natural stone, fiberglass, glass block, pottery, mirrors, and more. Patented thin wall design cuts three times faster than other diamond hole saws. Century Diamond Grit Hole Saws will cut 4X faster than other brands. Requires water lubrication to ensure a longer cutting life. See package for usage tips and instructions.