BCLONG 30Pcs 0.4-3.0mm Micro Lapidary Diamond Drill Bits Carving Burrs Tools For Stone

Features: *100% brand new and high quality. *Made of high-quality materials durable and practical *It can be installed on electronic grinders crane grinders and hand drills (not provided here). *Suitable for drilling holes in jewelry gems glass marble ceramic tiles or granite. *Used for drilling engraving precision grinding and internal grinding cemented carbide for ceramics glass gems alloys and many other abrasives. *Used with water as lubricant *Note: When engraving cold water must be used to cool the workpiece and polish the grinding head and there must be no water in an instant *Do not use an electric drill when the machine is hammering *If you are trying to drill through a material with a thickness of more than 6mm it is recommended to use the double-sided drilling through method. First drill on one side and then flip the stone to the other side to complete the drilling. Specifications: *Pen shape: cylindrical tip *Head diameter: 0.4mm / 0.5mm / 0.6mm / 0.8mm / 1mm / 1.2mm / 1.5mm / 1.8mm / 2mm / 2.5mm/3mm *Total length: 42mm (1-21/32inch) *Drilling depth: 3-6mm depth * Shank diameter: 2.35mm (3/32inch) *Material: metal diamond *Quantity: 30 pieces *Speed 5000-50000r/min Package Contents: 30*drill Conversion: 1inch = 2.54cm 1cm = 0.393inches Note: 1. The real color of the item may be slightly different from the pictures shown on website caused by many factors such as brightness of your monitor and light brightness. 2. Please allow slight manual measurement deviation for the data.