6203.43.01.00 - Containing 15 percent or more by weight of down and waterfowl plumage and of which down comprises 35 percent or more by weight; containing 10 percent or more by weight of down

This HTS code, 6203.43.01.00, specifically classifies men's or boys' trousers, bib and brace overalls, breeches, and shorts that are made of synthetic fibers. A key defining characteristic of this category is that these garments must contain 15 percent or more by weight of down and waterfowl plumage, with down itself comprising 35 percent or more of that plumage by weight. Additionally, the garments must contain at least 10 percent by weight of down overall. This emphasis on high down content signifies a focus on garments designed for insulation and warmth, often associated with specific types of outerwear.

The primary distinction of this category lies in its precise down and plumage content requirements, distinguishing it from other "Of synthetic fibers" trousers and shorts. While other sibling categories under "Of synthetic fibers" might cover general-purpose trousers or shorts made from synthetic materials, this classification is narrowly focused on garments where down and waterfowl plumage are a substantial insulating component. This granular detail ensures that specialized garments with advanced thermal properties are correctly identified.

As this is a leaf node within the HTS, there are no further subcategories for this specific code. Therefore, the classification ends with these detailed material composition criteria. Importers and exporters should carefully verify the weight percentage of down and waterfowl plumage in their synthetic fiber garments to ensure accurate classification under this specific HTS code. Examples of goods that would fall under this code include highly insulated ski pants or down-filled performance shorts made predominantly from synthetic outer shells.