Linghhang - Jewelry Drill Bit (1.6-1.8mm) - 20pcs/Pack 1mm Diamond Coated Lapidary Drill Bits, Solid Needle Bit, Agate Drill Bit for Agate Jewelry

General description High quality diamond powder lapidary drill bits, precise and durable. Ideal for drilling holes in materials for jewelry, ceramics, jade, agate, glass, amber, and semiconductors. Technical specifications Size: 1.6-1.8mm Quantity: 20pcs/Pack Usage The higher the speed of the drilling machine, the better the effect of the drill bits. The speed of the drilling machine should reach 2000 rpm when using these drill bits. Use cold water during the drilling operation. If the drill bit becomes dull after multiple uses, you can cut the top slightly with pliers to restore sharpness.