IEC 61386-23:2021 is available as IEC 61386-23:2021 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition. IEC 61386-23:2021 specifies the requirements for flexible conduit systems. This document is to be used in conjunction with IEC 61386-1:2008 and IEC 61386-1:2008/AMD1:2017. This second edition cancels and replaces the first edition published in 2002. This edition constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition: - Annex AA has been added to provide guidance on the application of a constantly increasing force.