Specifications: Diameter: 6/8/10/12mm, Material: Diamond, Handle: 6.35mm hexagonal handle, Diamond area width: 10mm, Color: Black, Application: Open holes for drilling granite and marble, masonry, concrete, ceramic tiles/ceramics, glass, hard plastic....., Features: Built-in waxing cooling, dry drilling without water. Efficient and versatile drilling. Durable and wear-resistant, WARNING: When using a brazed diamond hole saw, the speed of the electric tool should not be less than 2000 revolutions per minute, and the faster the speed, the better the effect. The bit should not be pressed down with force, otherwise it may be damaged. Packaging included: 4 drill bits, Note: Please allow for minor errors due to manual measurement. For different monitor displays, there may be a slight difference in color.