Drilax Diamond Drill Bit Hole Saw 1-3/8 inch Core Glass, Marble, Granite, Ceramic Porcelain Tiles DIY Drill Bit Size: 1-3/8 inch PREMIUM QUALITY, LONG LASTING, TALL (DEEPER CUTS) Diamond Hole Saw Drill Bit Tool. TOOL Diameter is 1 3/8 inches. SAVE OVER 80 Percent compared to your local hardware store. SPECIAL FEATURE : INCREASED DEPTH of CUT. These hole saws are 20 Percent TALLER (deeper) than most competitors. You can drill through thicker materials with this tool. 1 1/4 inch counter-tops are no problem. Shank size is 3/8 inch for common drills (corded electric, cordless rechargeable, upright, other rotary tools) EXCELLENT RESULTS in Granite, Ceramic and Porcelain Tiles, Glass, Bottles, Fish Tanks, Marble, Quartz, Slate, and many types of Stones. DRILAX BUILT QUALITY. WE ARE HERE TO HELP. Shank sizes vary, maximum shank is 3/8" suitable for all common electric drillers.