... flute 2.HRC55 3.Superior quality 4.Durable in use end mills1.Carbide square 4 flute2.Composition: 88% Wc, ... um6.Processing : middle-speed7.Hardness: HRC558.Made by world latest 5-AXIS CNC tools grinder, promise the quality ... , and improve the tools life much.10.Each end mill is inspected by Zoller measuring and inspected machine ... cast steel, tooling steel, mould steel, heattreament steel. end mills