9902.10.81 - Poly(1,1,2,2-tetrafluoro-2-[(trifluoroethenyl)oxy]ethanesulfonyl fluoride-co-tetrafluoroethylene) lithium salt (CAS No. 1687740-67-5) (provided for in subheading 3904.69.50)

This HTS classification, 9902.10.81, specifically designates a particular lithium salt of a fluoropolymer. The detailed chemical name, Poly(1,1,2,2-tetrafluoro-2-[(trifluoroethenyl)oxy]ethanesulfonyl fluoride-co-tetrafluoroethylene) lithium salt (CAS No. 1687740-67-5), precisely identifies the substance. Its inclusion under Chapter 99 signifies that this classification is subject to temporary legislation, trade agreement modifications, or additional import restrictions, rather than permanent tariff treatment. While its primary material composition aligns it with broader polymer classifications, its specific chemical structure and designation under Chapter 99 set it apart.

Unlike the numerous sibling categories that cover a vast array of goods from live animals to manufactured products, 9902.10.81 focuses on a highly specialized chemical compound. The "provided for in subheading 3904.69.50" note indicates its primary tariff classification before the application of these temporary measures. This allows for specific control and reporting requirements for this particular fluoropolymer salt when imported.

As this is a leaf node, there are no further subdivisions within 9902.10.81. Classification at this level is definitive for the specified substance. Importers must ensure that the imported material precisely matches the chemical description and CAS number provided, as variations in chemical composition or form could necessitate classification under a different HTS code, potentially outside of these temporary provisions.