Check the listing for details. 20Pcs 2mm Diamond Coated Lapidary Drill Hole Needle Solid Bits 1# Jewelry Tools. Condition: New. Listed at 14.99 USD. 店小秘助手 20Pcs 2 mm Diamond Coated Lapidary Drill Hole Needle Solid Bits for Jewelry Agate Gemstone Code LYDKZ-2.0-20Pcs-1# Product Description: Product Name: Lapidary Diamond Drill Bits, Diamond Drill Bits for Stone Jewelry Head Diameter:2.0mm Shank Diameter:1.0mm Total Length:52mm Quantity:Total 20Pcs Drilling speed:Drill a Hole in Seconds Use with water as a lubricant Must drop water or put the stones in the water, during drilling hole operation. Max speed: 18000 RPM The higher the speed of machine, the effect of drilling hole is better Application: suitable for use in drill hole on the Jewelry, Gems, jade, agate, amber, beeswax, crystal Suitable Machine: high speed bench drill. If you using normal bench drill ( speed below 10000 RPM ), the drill needle is easy to be broken. Note: The drilling hole needles are producted from factory directily, there is rust on needlersquos handle, but not influence use. Quick Tips 1. During drilling operation, with machines can't use more than 1 kg of strength to press the needle, because the diameter of handle is very small, too big power will broken needle. 2. Suggest you use the machine to drilling hole, just like the chicken peck rice, drilling hole after a few seconds, lift up once, and then press the continue to drill. We Can List Any Size (Head Diameter 1.0mm/1.2mm/1.4mm/1.6mm/1.8mm/2.0mm/2.2mm ) & Amount Of This Product. We will send out your order within 1-2 days after payment has been received and cleared.