Tariff schedule amendments revise commodity classification and customs duty rates, adding new headings and clarified product definitions. The Schedule amends the First Schedule of the Customs Tariff Act by substituting, inserting and omitting headings, subheadings, tariff items and Notes to reclassify goods, add new product categories (including insects, microbial fats, nicotine-inhalation products and unmanned aircraft), refine definitional and interpretative Notes, and prescribe specific customs duty rates for numerous tariff lines, thereby modifying classification precedence and tariff treatment across multiple chapters and sections of the Nomenclature.