About This Tough Dry Diamond Hole Cutter ??drilling perfect 2-1/2" Diameter holes in soft wall tiles and very hard floor tiles such as Porcelain, Ceramic Marble, Granite tiles, Natural stone High Quality Diamond Core Bit ??Vacuum brazed diamond (height 15mm) for fast and smooth cutting and longer lifetime; Slot in the side for easy removal of debris; Max working depth 2" Fit most tools ??Hole Saw Bit is built with a female 5/8-11 thread to attach directly to an angle grinder; thread to 3/8 Hex shank adaptor is included for use with high-speed electric drills (hammer action must be turned OFF) User Tips ??Start the tool at a high speed between 10,000 and 14,000 rpm, let the bit touch the tile in a 45-degree angle to get position slot, then bring the tool up right slowly and move in circle motion; If it's getting too hot, dip in water or stop to cool Easy to Use ??you can let the diamond hole cutter do the cutting job, no extra pressure is required; just move the tool in a swiveling motion to remove the debris and prevent diamond wear out Overview Material : Diamond Brand : DKIBBITH Color : Black Style : Compact Compatible Devices : Angle Grinders, Electric Drills