... "). Used for shaping, smoothing & removal hardened steel. Carbide rotary burr 8pcs set,carbide rotary fileShank Diameter: 6mm, 6. 35mm(1/4"), or ... upon request Packing: 8pcs/set, or upon request.Used for shaping, smoothing & removal hardened steel ... , fired ceramics, plastics, hardwoods and so on. Tungsten carbide burr set 8pcs set carbide burrs