Yosoo 15pcs Diamond tool drill bit hole saw set for glass ceramic marble from 6-50mm This diamond coated core drill bit removes a complete circle from glass, tiles, marble, granite, cer Can be used with a standard electric drill( Excluding in this item ) Easy to use, high quality,good performance, long life - Excellent for making clean and accurate hole Always use lubrication (water ), otherwise the diamond core drill will burn - Start your hole diagon Package Includes: 1 x 15pcs Diamond Coated Hole Saw Drill Bits