5101.21.65.00 - Unimproved wool; other wool, not finer than 46s.

This HTS classification, 5101.21.65.00, pertains to unimproved wool that has been degreased but not carbonized, and is not finer than 46s (a measure of wool fineness). This category specifically covers "other" wool within the shorn wool, degreased, not carbonized group. The defining characteristic here is the fineness of the wool; it falls outside the scope of finer wools within this grouping.

The distinction between this subcategory and its sibling, 5101.21.70.00, lies in the specific designation of "other." While both are degreased, not carbonized, shorn wool that is not finer than 46s, the 5101.21.65.00 category captures a specific subset of this wool. This might relate to specific processing steps, origin, or further physical characteristics that differentiate it from the broader "other" category.

As this is a leaf node in the HTS, there are no further subdivisions. Therefore, the classification hinges on the precise application of the "not finer than 46s" criterion and any other implicit or explicit differentiators that lead to this specific code as opposed to the broader "other" sibling category. Importers and exporters should meticulously verify the specific characteristics of their wool to ensure accurate application.