Lenox Tools 121085DGDS Diamond Grit Hole Saw D/S-5DG, 5/16-Inch or 7.9mm N/A Imported Each LENOX hole saw has a continuous, brazed edge that lasts longer in tile and stone The diamond-tip hole saw uses a low-torque design that requires little pressure for fast cutting An over-sized slot in the LENOX Diamond hole saw allows for easy plug removal 5/16-inch diameter 90-day limited warranty