[MATERIAL] - Diamond coated steel (HSS) is made by spiral technology, has both toughness and hardness, is not easy to break. The drill bit is sharp and easy to remove chips. [APPLICABLE MACHINE] - Widely used in rotary machines such as hand drills, drill presses, flexible drills, bench drills and hanging grinders. [APPLICATION] - Suitable for drilling small holes on glass, metal, shells, jade, pearls, marbles, stones, drywall and wires. Due to the different hardness of the material, the effect is also different. [NOTICE] - When drilling, it is necessary to add cutting fluid in time for lubrication and cooling, which can achieve better drill hole wall, prolong the service life and drilling accuracy. Shank Diameter: 1.0 mm / 0.04 inch Drill Bit Diameter: 1.0 mm / 0.04 inch 1. Cannot be used for drilling wood. The diamond drill bit generates a lot of heat during high-speed rotation, and the heat will burn the wood. 2. Low-speed drilling is very easy to break the drill bit or drop the