5206.21Subheading
Cotton yarn; (not sewing thread), single, of combed fibres, less than 85% by weight of cotton, measuring 714.29 decitex or more, (not exceeding 14 metric number), not for retail sale
Section XI — Textiles and textile articles
This is a 6-digit subheading — the most specific level of the international HS. Country tariff schedules extend it further; the US tariff lines (HTS) below refine it to 8–10 digits for duty purposes.
US tariff lines for this subheading are not in the bundled starter dataset yet — the full HTS schedule is coming soon. You can still search by code in the tariff simulator.