Description Features: The diamond coated core drill bit removes a complete circle from glass, tiles, marble, granite, ceramic or other materials and only needs water for lubrication. Comes with different sizes for multiple purposes. Can be used with a standard electric drill. Made from premium metal with diamond coating, it is of high hardness, wear-resistant and durable in use. Easy to use. Just start your hole diagonally and make a round trace and then hold drill straight. Always use lubrication (water), otherwise the diamond core drill will burn. Specifications: Condition: 100% Brand New Material: Metal with Diamond Coating Open Hole Size: 6mm/0.24in, 8mm/0.31in, 10mm/0.39in, 14mm/0.55in, 16mm/0.63in, 18mm/0.71in, 22mm/0.87in, 35mm/1.38in, 40mm/1.57in, 50mm/1.97in Total Length: Approx. 5.3cm/2.09in Quantity: 10pcs Weight: Approx. 352g Package Included: 10 * Diamond Coated Hole Saw Drill Bits 1The diamond coated core drill bit removes a complete circle from glass, tiles, marble, granite, ceramic or other materials and only needs water for lubrication 2Comes with different sizes for multiple purposes. Can be used with a standard electric drill 3Made from premium metal with diamond coating, it is of high hardness, wear-resistant and durable in use 4Easy to use. Just start your hole diagonally and make a round trace and then hold drill straight 5Always use lubrication (water), otherwise the diamond core drill will burn