Three Different SizesThe package includes three cone drill bits of size 4-12mm, 4-20mm, 4-32mm, with different sizes to meet different drilling requirements, universal standard 6.3mm hexagonal shank diameter, compatible with a wide range of drilling machine models, can be used for aluminum, wood, thin iron, PVC materials, plastic boards, etc. Reliable MaterialMade of high quality steel with titanium coating to increase the surface hardness and improve the sharpness and durability of the drill bit, which reduces friction and excessive heat during use, and the double helix design prevents slippage and helps move chips during work. The 118 tip design allows you to drill from multiple angles. Precise CuttingEach tapered drill bit is laser marked for precise selection, the sharp drill bit cuts more precisely into the material without abrasion, ensures optimal hole spacing, and as the hole diameter increases, the rotation speed is reduced to ensure safe cutting. Double Spiral DesignThe double spiral design allows for more uniform drilling and effectively avoids resistance or stagnation during use. It can be used for drilling or reaming, and has faster speed and accuracy to ensure the clarity of drilling or reaming. Improve work efficiency Easy to useIn order to effectively extend the service life of the drill bit and avoid softening or discoloration, the drill bit should be added with water or cutting fluid to keep it at a low temperature when working. Clean the surface in time after use to avoid corrosion caused by other substances.