Description:This is a brand new itemThis diamond coated core drill bit removes a complete circle from glass， tiles， marble， granite， ceramic or other materials and only needs water for lubricationCan be used with a standard electric drill( Excluding in this item )Easy to use， high quality，good performance， long lifeExcellent for making clean and accurate hole on glass ， tile and marbleAlways use lubrication (water )， otherwise the diamond core drill will burnStart your hole diagonally， make a round trace and then hold drill straightPopular Sizes:3/4" (20mm)1" (25mm)1 1/4" (32mm) 1 3/8" (35mm)1 1/2" (38mm)Package Includes:1 x 5pcs Diamond Coated Hole Saw Drill Bits