IEC 60068-2-21:2021 is applicable to all electrical and electronic components whose terminations or integral mounting devices are liable to be submitted to stresses during normal assembly or handling operations and is also applicable to surface mount devices (SMDs). This seventh edition cancels and replaces the sixth edition, published in 2006, and IEC 60068‑2‑77:1999. This edition constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition: ;lt;ol style="list-style-type:lower-alpha";gt; ;lt;li;gt;integration of parts of IEC 60068-2-77 (see Annex X); IEC 60068-2-77 is withdrawn with the publication of this document;;lt;/li;gt; ;lt;li;gt;Annex X is added to show the correlation of the clauses and subclauses in this edition of IEC 60068-2-21 with the clauses in IEC 60068-2-21:2006 and IEC 60068-2-77:1999.;lt;/li;gt; ;lt;/ol;gt;