【Gemstone Drill Bits】Head Diameter: 1mm; Total length:36mm; Shank diameter:0.6mm; Quantity:20Pcs

【Drill Holes】Use cold water during the drilling hole operation, use high-speed(Up 20000 RPM) to drill holes with our drill bits. The higher speed of drilling machine, the better effect of drilling bits.

【High Quality】Made from diamond powder, high-quality, precise and durable to use.

【Widely Use】Idea for drill holes on the jewelry, ceramic, jade, agate, glass, amber and semiconductor materials etc.

【Sharp Bits】If you use the drill bit for many times, it will not be very sharp than the first time using.You could cut a little the top of it with plier, it will become sharp again.