7019.63.40.30 - Silica filament fabric of filaments with silica content greater than 93 percent (622)

This HTS category, 7019.63.40.30, specifically classifies silica filament fabrics composed of filaments with a silica content exceeding 93 percent. These fabrics are characterized by their high purity silica composition, contributing to their unique properties such as exceptional heat resistance and chemical inertness. They are typically used in high-temperature industrial applications, advanced composites, or specialized filtration systems where these specialized material characteristics are paramount.

While sibling category 7019.63.40.60 also falls under "Other" mechanically bonded, closed woven, plain weave, not colored fabrics, this specific subcategory is distinguished by the defining characteristic of a high silica content (greater than 93%) in its constituent filaments. This elevated silica content sets it apart from other silica filament fabrics that may have a lower silica concentration or are made from different types of glass filaments. The precise chemical composition is the key differentiator at this level.

As a leaf node, this classification does not have further subdivisions. Therefore, classification into this subcategory relies heavily on the direct verification of the filament's silica content, alongside the established criteria of being a woven fabric, mechanically bonded, plain weave, and uncolored. Importers and exporters should ensure their documentation clearly supports the high silica content for accurate classification.