Foredom Carbide Ball, 1/4 inch Dia., 1/8 inch Shank. 1 3/4 Inches Overall Length, Style A-B-2. Carbide bur with standard flutes are used for easy material removal and leave a smooth finish. These burs are ideal for use on hard wood and most metals including stainless steel, steel alloys, cast iron, etc. 35000 RPM Max Speed. Made in USA.