#10Pcs #Diamond #Coated #Core #Hole #Saw #Drill #Bit #Set #Tools 100% brand new and high quality 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. Size: 6mm/0.23", 8mm/0.31", 10mm/0.39", 12mm/0.47", 14mm/0.55", 16mm/0.62", 18mm/0.7", 20mm/0.78", 22mm/0.86", 30mm/1.17" Quantity: 10 pcs Note: Due to the difference between different monitors, the picture may not reflect the actual color of the item. Please understand, Thank you.