External 60° partial profile, laydown threading inserts. IR/L - Ground periphery and rake, ERB - with a chipformer and peripherally ground, ERM - With a chipformer. Application: general applications A tough submicron grain size substrate with a PVD coating, recommended for general use for diverse operations on materials such as steels, alloy steels, austenitic stainless steel and high temperature alloys at a wide range of cutting speeds. Features high wear resistance and chipping durability.