High Quality: The PCB drill bits set are made of high-quality, which is high wear resistance, high hardness, anti-impairment. Seismic design on the blade edge enables it to stay stable during engraving. Various Sizes: 1/8 Inch shank; bits diameter: 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1.0mm, 1.1mm, 1.2mm, 1.3mm, 1.4mm, 1.5m, 1.6mm, 1.7mm, 1.8mm, 1.9mm, 2.0mm, 2.1mm, 2.2mm, 2.3mm, 2.4mm, 2.5mm, 2.6mm, 2.7mm, 2.8mm, 2.9mm, 3.0mm. This Set contains 30 different size drill bits diameter, each size having1 pcs. Advantage: With spiral flute , these PCB drill bits can reduce cutting force and prevent the drill from broken and improve accuracy. They work quickly and cleanly, with no glitches or scrap left. Application: Suitable for amber beeswax, printed circuit boards, 3D printer nozzle cleaning, Acrylic Glass, bakelite, CNC engraving, jewelry, plastic, and other precise drilling. 30-piece Combo Set: There are 3 sets of drill bits (Set A: 0.1mm-1.0mm; Set B: