Diamond kit specializes in drilling hard materials such as marble, tile, granite, glass, etc. (not suitable for wood). Glass concrete drill bit can be used for drilling concrete, glass, tile, ceramic, wood, brick.Ceramic drill bit have built-in cooling wax, which can effectively transfer heat and cool the contact surface. Water can also be used as a supplementary coolant to extend the life of the drill bit.Diamond coating improves drilling speed and does not drop the drill, long-lasting and durable. The drill body is forged with high-strength metal, not easy to deformation, can easily punch holes.Round shank drill bits are suitable for most machines such as hand drills, angle grinders, bench top drills. Depth marks are especially useful for precise drilling.color:BlackMaterial:steelPackage Contents:1 x dry diamond drill bit 5 mm (3/16inch) diameter1 x dry diamond drill bit 6 mm (1/4inch) diameter1 x dry diamond drill bit 8 mm (5/16inch) diameter1 x dry diamond drill bit 10 mm (3/8inch) diameter1 x dry diamond drill bit 12 mm (1/2inch) diameter1 x dry diamond drill bit 14 mm (9/16inch) diameter1 x dry diamond drill bit 16 mm (5/8inch) diameter1 x Hex Shank Drill Bit 3 mm (1/8inch) diameter1 x Hex Shank Drill Bit 4 mm (5/32inch) diameterOnly the above package content, other products are not included.Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.