IEC 62561-4:2023 is available as IEC 62561-4:2023 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition.IEC 62561-4:2023 deals with the requirements and tests for metallic and non-metallic conductor fasteners that are used to retain and support the air-termination, down-conductor and earth-termination systems. This third edition cancels and replaces the second edition published in 2017. This edition constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition:a) alignment with the latest edition of ISO IEC 60068-2-52:2017 relating to salt mist atmosphere treatment;b) alignment with the new edition of ISO 22479:2019 relating to humid sulphurous atmosphere treatment;c) new normative annex for the applicability of previous tests.