... strength :4000 Micro -Diameter Flat End Mill And Ball Nose End Mill Grain Size :05 ... :4000 1 Suitable for Copper,Cast Iron,Carbon steel,and Mould steel processing.Stainless steel,Titanium Alloy ... ,Tool steel ,and Heat-treated steel processing 2 Main features ... inclease the smoothness,reduce the rubbing coefficient, and improve the lathe efficiency ,save more production ...