5509.99.20.00 - Single yarn (607)

This HTS category, 5509.99.20.00, encompasses single yarns composed primarily or solely of synthetic staple fibers that are mixed with artificial staple fibers. These yarns are not put up for retail sale, meaning they are typically sold in bulk for further manufacturing processes. The "single yarn" designation is crucial, indicating a single strand of spun fibers, as opposed to yarns that have been twisted together.

The primary distinction between this category and its sibling, 5509.99.40.00, lies in the construction of the yarn. While both involve synthetic staple fibers mixed with artificial staple fibers, this classification specifically covers *single* yarns. Its sibling category, conversely, deals with *multiple (folded) or cabled* yarns, which are formed by twisting two or more single yarns together. Therefore, the number of individual yarn strands twisted together is the key differentiator.

As this is a leaf node in the HTS, there are no further subcategories to introduce. Classification within 5509.99.20.00 is finalized once it's determined the yarn is single, made of synthetic staple fibers mixed mainly or solely with artificial staple fibers, and not presented for retail sale. Examples of goods falling here would include undyed or dyed single yarns used in the production of fabrics for apparel, home furnishings, or industrial textiles, provided they meet the fiber composition and construction criteria.