Features: 1.Every product has a unique Manufacturing Part Number label on the inner package that proves it has been qualified,which include Part Number,Model Number and inspection date information;2.If you have any questions about the item,please provide us the Manufacturing Part Number for checking,your profits will be guaranteed.3.Metal Drill Bit: made of high-quality metal, which are reliable and durable.4.Diamond Burr Head: Drill bit with diamond burr head, suitable for drilling, carving, grinding and other work of jade, agate, emerald, pearl, shell.5.How to use: Use a drip device to cool the drill bit during the drilling process. If no water is added, the diamond on the tool bit will be graphitized due to overheating, which will quickly wear out and be scrapped.6.Drilling bit tool processes workpieces by grinding, please do not use too much force, the grinding powder is not easy to remove, and the tool is easy to be damaged.7.The package includes 100 drilling bit tools to meet your needs at one time.Safety instructions:1. Drill bit permanently enclosed in a cartridge or housing with less than 2mm of Drill bit exposeduFFFDuFFFD2. The Drill bit product is not use for people under 18 years.3. The item is only for industrialengraving, not hazardous article.Specifications:Material: Metal u0026 DiamondColor: Silver name: Size: 42.6x2.3mm/1.68x0.09inch (LxW)Shank diameter: 2.35mm/0.09inchHead diameter: 1mm /0.04inchSand length: 6-8mm /0.23-0.31inchWeight: 120gPackage include:100 x Diamond Burr Metal Bit