C.J. SHOP 10pcs Tungsten Steel Hard Alloy PCB CNC Drill Bits For Circuit Boards Print Carbide Micro Set Tool 0.1mm-1.0mm 0.3-1.2mm 1.1-2.0mm Material: Hard alloy (tungsten steel) Size: 0.1-1mm;? 0.3-1.2mm;? 1.1-2.0mm Shank Diameter: 3.175mm Suitable for circuit boards, electronic, SMT, mold, metal processing, telecommunications and other industries Can be used for drilling iron, glass fiber, etc.