6103.49.40 - Containing 70 percent or more by weight of silk or silk waste

This HTS category, 6103.49.40, specifically classifies knitted or crocheted trousers, bib and brace overalls, breeches, and shorts for men or boys that are predominantly composed of silk or silk waste, accounting for 70 percent or more by weight. These items are part of the broader classification for men's or boys' suits, ensembles, and separates under Chapter 61.

This classification distinguishes itself from its sibling category, 6103.49.80 ("Other"), by its precise material composition requirement of high silk content. It also differs from other potential categories within 6103.49 ("Of other textile materials") that might specify different primary fiber types, such as artificial fibers, by focusing exclusively on silk or silk waste as the dominant component.

Within this silk-predominant category, further subdivisions exist to differentiate between specific types of garments. The subcategories 6103.49.40.10 for trousers, breeches, and shorts, and 6103.49.40.20 for bib and brace overalls, allow for a more granular classification based on the particular garment style. This ensures accurate statistical reporting and tariff application based on the exact item being imported or exported.