5107.10 - Containing 85 percent or more by weight of wool:

This HTS category, 5107.10, specifically covers yarns spun from combed wool that are not intended for retail sale. The defining characteristic of these yarns is their high wool content, requiring them to contain 85 percent or more by weight of wool. This classification is relevant for bulk shipments or yarns intended for further industrial processing, rather than those packaged for direct consumer purchase.

It's important to distinguish 5107.10 from its sibling category, 5107.20, which covers yarns containing less than 85 percent by weight of wool. The precise percentage of wool content is the critical factor for differentiating between these two categories, ensuring that yarns with a predominant wool composition are correctly classified under 5107.10.

Within 5107.10, two subcategories exist to further refine the classification based on the physical characteristics of the wool fiber. The first, 5107.10.30.00, pertains to yarns made from wool fiber with an average diameter of 18.5 microns or less. This designation often relates to finer wools, which can impact the yarn's quality and end-use. The second subcategory, 5107.10.60.00, is a residual category for all other yarns within 5107.10 that do not meet the specific micron diameter criteria.