Rotary File Set, Rotary Tool Accessory Type Rotary File, Bit Material Alloy Steel, Shape Ball, Bullet, Cone, Cylinder, Max. Speed 2,500 RPM, Shank Diameter 1/4 in, Mount Type Mounted, Overall Length 2 in, Burr Diameter 1/4 in, 1/2 in, Head Length 1/2 in, 7/8 in, 1 in, Head Width 1/4 in, 1/2 in, Material Application Bronze, Iron, Mild Steel, Plastic, Soft Metal, Wood