MaterialsThe drill bit set is made of alloy as the raw material. The oxynitride process of the cutter head strengthens the hardness of the drill bit. Surface electrophoretic painting process The drill set is comprehensive and rust-proof grinding treatment, clean and sharp without burrs. The drill is more wear-resistant and more durable. Fully automated polishing, polishing is fully automated, each one is unique. Unique cross angle design Small incision resistance, stable drilling functionality, fast speed, without breaking the border. Neat opening, smooth, no broken edges, no wobble phenomenon, peel off easily.5 different sizes Suitable for your different needs. It can be installed in the general electric hand drill, bench drill. The clamping range of the machine drill is 10mm and above.