This Part 8-1 of the international standard series IEC 60404 specifies minimum values for the principal magnetic properties of, and dimensional tolerances for, technically important magnetically hard materials (permanent magnets). Some additional physical data and mechanical reference values concerning the magnetic materials are given for information and comparison purposes are also given in tabular form. With the current revision of the standard recently developed anisotropic Sm-Fe-N bonded magnets have been included as well as high energy ferrites with La and Co as substituents. The International Standard IEC 60404-8-1 Ed. 2.1 "Magnetic materials - Part 8-1: Specifications for individual materials - Magnetically hard materials" was published in July 2004. The present revision of IEC 60404-8-1 covers the recently developed anisotropic Sm-Fe-N bonded magnets as well as the high-energy ferrites with La and Co as substituents, which have been introduced into the application of permanent magnets. Furthermore, corrections have been made to the previous edition to improve the adaptation to IEC 60404-5. The square shape was introduced by the value HD. The responsible committee is DKE/K 171 "Magnetische Legierungen und Stahl" ("Magnetic alloys and steels") of the DKE (German Commission for Electrical, Electronic and Information Technologies) at DIN and VDE.