Alfa Tools cobalt M42 roughing end mills. Feature a sinusoidal chip breaker form, which produces small chips, allowing them to run at faster feed rates than conventional tools, resulting in high material removal rates. Designed to machine difficult and abrasive materials ranging from medium to the highest hardness levels Machin able by high-speed steel. 8% cobalt content assures high edge hardness at elevated temperatures. Large core diameter provides rigidity and reduces deflection.