5509.99.40.00 - Multiple (folded) or cabled yarn (607)

This HTS classification, 5509.99.40.00, covers multiple-folded or cabled yarn spun from synthetic staple fibers. These yarns are not intended for retail sale and are distinct from single yarns. The "multiple (folded) or cabled" designation signifies that two or more single yarns have been twisted together to form a stronger, more complex yarn structure. This category specifically addresses such constructions where the primary components are synthetic staple fibers.

The key differentiator from its sibling category, 5509.99.20.00 ("Single yarn"), lies in the construction of the yarn. While the sibling refers to a single strand of spun fiber, this classification is for yarns formed by combining multiple single strands through twisting. This folding or cabling process alters the yarn's characteristics, making it suitable for different end uses and requiring a separate classification to accurately reflect its manufacturing and structure.

As this is a leaf node, there are no further subdivisions under this HTS code. Therefore, the focus for classification within 5509.99.40.00 is on ensuring the yarn meets the criteria of being multiple (folded) or cabled, is made from synthetic staple fibers, and is not put up for retail sale. Examples would include yarns intended for industrial fabrics, ropes, or other bulk textile applications where the strength and structure of a folded or cabled yarn are paramount.