6203.43.09 - Containing 36 percent or more by weight of wool or fine animal hair

This HTS category, 6203.43.09, specifically classifies men's or boys' trousers and breeches crafted from synthetic fibers that are not knitted or crocheted. The defining characteristic for inclusion here is the material composition, where synthetic fibers constitute the primary textile component. This heading focuses on garments designed for wear, excluding those intended for specialized athletic or recreational performance where specific technical features might warrant a different classification.

Distinguishing this category from its siblings, particularly the "Shorts" subcategory (6203.43.09.30), is the length of the garment. While both fall under the broader umbrella of "Trousers, bib and brace overalls, breeches and shorts," this specific code isolates the longer forms of legwear. The "Other" sibling at this level would typically encompass items not fitting into the more defined subcategories, making the distinction between trousers/breeches and shorts a key differentiator.

The subcategory, 6203.43.09.30, represents a further subdivision, specifically for men's or boys' shorts made from synthetic fibers. This demonstrates the granular nature of HTS classification, allowing for precise identification based on garment style and length within the broader category of synthetic trousers, bib and brace overalls, breeches, and shorts.