This part of IEC 60404 defines the grades of Fe-based amorphous strip delivered in the semi-processed state, i.e. without final heat treatment, of nominal thickness 0,025 mm. Other nominal thicknesses in the range from 0,020 mm to 0,030 mm can be specified by agreement between the manufacturer and the purchaser at the time of enquiry and order. In particular, it gives general requirements, magnetic properties, geometric characteristics, tolerances and technological characteristics, as well as inspection procedures. This document applies to the rapidly-solidified Fe-based amorphous strip supplied in coils with as-cast edges and intended for the construction of magnetic circuits. The grades are grouped into two classes: – conventional grades; – high permeability grades. They correspond to Class I1 of IEC 60404-1.