IEC 60401-2:2009 presents a method for defining the designation nomenclature for the major physical attributes of soft ferrite core shapes. The purpose of this standard is to facilitate uniform usage of dimensional characters by manufacturers, specifiers, and users when describing core dimensions on drawings, in tables, and on catalogue specification sheets. This edition includes the following significant technical changes with respect to the previous edition: New ferrite core shapes 'half pot core for inductive proximity switches and PM core' in accordance with IEC 62317 series have been added respectively as Figure 13 and Figure 14 in Clause 5: core illustrations.