Ball Bur SD, Type Double, Shank Dia. 1/8 in, Head Dia. 1/4 in, Head Length 1/4 in, Included Angle Not Applicable, Overall Length 1 1/2 in, Trade Number SD-51, Head Shape Ball, Operating Speed - Maximum 70,000 RPM, List Number 815, Coating Bright (Uncoated), Head Material Carbide, Shank Material Hardened Steel