Customs tariff amendments: technical substitutions to First Schedule updating tariff codes and duty entries without revenue impact. The notification, exercising powers under section 11A, substitutes specified tariff entries across multiple chapters of the First Schedule to the Customs Tariff Act, 1975 and alters certain column (2) and column (4) entries, including a revised duty entry for tariff item 5211 49 90. The amendments are presented as technical corrections to tariff codes, headings and columnar descriptions to ensure accurate nomenclature and classification.