Amana Tool multi-helix tools are the Superstars of carbide end mills for professionals and hobbyists alike. The multiple helix eliminates Harmonic chatter, so critical when surface finishes part dimension tolerances and tool life are of the utmost importance. Premium aluminum titanium nitride (Altin) coating provides Quantum increases in productivity either in terms of speed or longevity with or without coolant. They are outstanding tools for peripheral milling and can take aggressive cuts along the full length of the overall flute Length with no issues. They last much longer than general Purpose end mills partly because they are coated partly because they Dampen vibration which tends to break a sharp cutting edge down very quickly. For use with manual and automatic milling machines, as well as the most sophisticated CNC machines.#51605, Direction Up-cut, (D) diameter 1/4, (r) radius 0.015, (b) Cutting height 5/8, (D) shank 1/4, overall length (L) 2-1/2, Type Corner radius bottom, flutes 4, 51605 CNC spiral multi-helix corner radius bottom 1/4 dia x 5/8 x 1/4 shank x 0.015 radius solid carbide Altin coated Up-cut end mill