25mm (1") Diameter Heavy Duty Diamond Segments Core Drill Bit hole Saw With Pilot Drill Bit 1" Diameter, HEAVY DUTY DIAMOND COATED CORE SAW WITH PILOT DRILL BIT Size: 1" outside diameter, 3/8" shank, 2-1/2" cutting depth. Overall Lenght: 4-1/4" Removes a complete circle from rock, granite, marble, tile, porcelain, concrete and other materials Only needs water for lubrication