1. Excellent Material: Made of carbon steel, and the surface is hardened and treated to be black for corrosion resistance, high hardness, abrasion resistance, and long life. 2. (Make a variety of needs) Body Length: Approx. 2.2 - 2.3 inches (56 - 58 mm), Shaft 0.25 inches (6.35 mm); Package Contents: 10 pieces; Head Shape: Cylinder, Tip cylinder, Sphere, Egg Shape, Bullet Shape, Oval Shape, Taper, Inverted Cone, Square and Small Bullets. Versatile and suitable for a variety of working situations. 3. Compatible models: All electric drills, air grinders, and electric tools that can be used to hold 0.25 inch (6.35 mm) shafts. 4. Easy to use: High processing efficiency, higher efficiency than manual files, and all metal materials ensure long service life. Safe and reliable, reduce labor strength 5. Uses: Rotating file is suitable for carving, polishing, and processing of Bodhi etc. Suitable for most small rotary tools, suitable for DIY enthusiasts and craft enthusiasts.