Product name: For PCB drill bit set Features: 1. The appearance is neat and burr-free Double helix is ​​more resistant to vibration than single , not prone to chipping, large chip removal capacity, and high processing efficiency 2. Tungsten steel drill is easy to use Precision grinding technology, strong wear resistance, high hardness 3. Good chip removal and high durability Double-edged milling has sharp cutting edge, fast chip removal, high durability and no cutting Two highlights 1. Positioning ring Humanized positioning ring box design reduces the debugging time of the machine 2. Packing box Better protection of the tip from damage during transportation Precautions: 1. When punching, it should be vertical, not too hard, slowly twist it in one direction, and the needle should not be bent or pried, otherwise it will be easily damaged! 2. Do not clamp it on the hand drill to rotate at high speed to punch holes, otherwise the amber will collapse. 3. When punching, pay attention to cleaning the surrounding powder at any time while rotating. 4. Grasp the tail of the drill bit and rotate it slowly to drill the hole. When you are about to drill through, pay special attention to reducing the speed and strength. 5. If you feel the needle is tight when rotating, please withdraw the needle, clean the hole powder and re-enter! Size classification: 1.1-2mm, 0.1mm-1.0mm, 0.3-1.2mm, 0.6-1.5mm, 1.5-2.4mm, 2.1-3.0mm Packaging size: 8*6*1cm Weight: 40g Includes: one set