Drilax&trade; 5 Pcs Diamond Drill Bit Set 3/4", 1", 1-3/16", 1-3/8", 1-5/8" - Wet Cutting Tiles, Glass, Fish Tanks, Marble, Granite, Ceramic, Porcelain, Bottles, Quartz Sinks, Lot 5 Diamond Coated Core Hole Saws- Kitchen, Bathroom, Shower, Faucet Very High Quality Diamond Drilling Tool Set of 5 Different Sizes: 3/4", 1", 1-3/16", 1-3/8", 1-5/8" Over 80% cost savings compared to big box stores. Use with standard electric or battery drillers. There is no need for a center pilot drill. These tools do not have center pilot drills. Do NOT run dry. These Diamond Coated Tools will work best if you use water to keep the tools cool. Shank sizes vary, maximum shank is 3/8" - suitable for all common electric drillers.