Description:Long Tool Life: Made from tungsten carbide, high hardness, high wear resistance, high strength, resistance to bending, anti-impairment, long service life.Spiral Flute Bits: Spiral flute drill bits reduce cutting force and prevent drill broken, improve the drilling accuracy. Large drill bit chip space, chip resistance, chip smooth, small drilling heat.Precision: With with sharper cutting edge, milling groove and clean surface, the carbide PCB drill bits can work quickly and cleanly, no glitches or scrap left.Applications: Great for PC boards, plastics, fiberglass, wood, soft metals. Suitable for PCB drilling machines, engraving machine, CNC and high precision special drilling equipment.Tips: The drill bits are too tiny, so it is very fragile for handling. Please be careful and take good control of your CNC speed.