7019.61.90.30 - Silica filament fabric of filaments with silica content greater than 93 percent (622)

This HTS category, 7019.61.90.30, specifically classifies silica filament fabrics where the filaments themselves contain a silica content exceeding 93 percent. These fabrics are typically characterized by their high temperature resistance and chemical inertness, making them suitable for specialized industrial applications such as thermal insulation, filtration at elevated temperatures, and as reinforcement in high-performance composites. The defining characteristic for inclusion here is the high silica content within the glass filaments that constitute the fabric.

This classification is distinguished from its sibling category, 7019.61.90.60, which also falls under "Other" colored closed woven fabrics of rovings. While both are colored and woven from rovings, the key differentiator for 7019.61.90.30 is the specific high silica content requirement of the filaments (greater than 93 percent). The sibling category would encompass other colored woven fabrics of rovings that do not meet this specific high-silica filament criterion.

As this is a leaf node within the HTS, there are no further subcategories to introduce. Therefore, classification into this specific code hinges entirely on meeting the criteria of being a closed woven fabric of rovings, being colored, falling under the "Other" designation within colored fabrics, and crucially, possessing filaments with a silica content exceeding 93 percent. The presence of this high silica content is the primary determinant for distinguishing these specialized silica filament fabrics from other glass fiber woven fabrics at this level.