Welcome to toedge's shop [toedge] 6-30mm Marble Granite Ceramic Glass Core Drill Bits Diamond Hole Saw Drill Bits Features: This diamond coated core drill bit removes a complete circle from glass, tiles, marble, granite, ceramic or other materials and only needs water for lubrication. Can be used with a standard electric drill. Always use lubrication (water ), otherwise the diamond core drill will burn. Start your hole diagonally, make a round trace and then hold drill straight. Material: Diamond Application:Drill for drilling glass, ceramic sintering, stone, stone, agate, shell, hard and brittle materials using tile etc. Product using: granite, marble, stone, ceramic tile, floor tile and other hard broken Specifications: Material:metal and diamond shank size:5-8mm Package Included: 1 x Diamond Coated Hole Saw Drill Bits