6207.91 - Of cotton:

This HTS category, 6207.91, specifically covers men's or boys' undergarments and similar articles when they are made predominantly of cotton. This includes items such as singlets, other undershirts, underpants, briefs, nightshirts, pajamas, bathrobes, dressing gowns, and other similar articles designed for indoor wear or as underclothing. The key distinguishing factor for classification within this heading is the material composition – cotton must be the primary textile material by weight or surface area.

Category 6207.91 is distinct from its sibling category, 6207.99, which is reserved for similar articles made of other textile materials, such as synthetic fibers, silk, wool, or linen. Therefore, when classifying an item under 6207.91, the definitive criterion is the presence of cotton as the principal component. This ensures accurate tariff application based on the material's origin and value.

Within category 6207.91, further subcategories exist to provide more granular classification. Subcategory 6207.91.10.00 is designated for bathrobes, dressing gowns, and similar articles, reflecting a specific type of garment within the broader cotton-based category. The remaining subcategory, 6207.91.30, encompasses all other cotton articles of men's or boys' apparel that do not fall under the more specific bathrobe and dressing gown designation, allowing for a comprehensive and organized tariff structure.