IEC 63093-1:2020 specifies the dimensions and allowable limits of surface irregularities of ferrite cores. It is intended that this document excludes ferrite cores which are specialty cores with limited use. Also, special cores which are only marginal variations upon standard cores are excluded. IEC publishes electrical standards for families of ferrite cores, as well as this series of dimensional standards for families of ferrite cores. Modifications to the ferrite cores listed in one type of standard are reflected in the other type. This document is considered as a general specification useful in the dialogue between ferrite core suppliers and users about surface irregularities. This first edition cancels and replaces the second edition of IEC 60424-1 published in 2015 and the first edition of IEC 62317-1 published in 2007. This edition constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous editions of IEC 60424-1 and IEC 62317-1: a) this document integrates IEC 60424-1 and IEC 62317-1.