3214.10.00.10 - Caulking compounds

This HTS category, 3214.10.00.10, specifically covers caulking compounds. These are malleable materials primarily used for sealing joints, gaps, or openings in construction and other applications to prevent the passage of air, water, or other substances. Typical examples include silicone caulks, acrylic latex caulks, polyurethane caulks, and polysulfide caulks, which are formulated to cure and form a flexible, weather-resistant seal.

It is important to distinguish caulking compounds from their sibling category, 3214.10.00.20, which is designated for "Other" mastics. While both fall under the broader heading of mastics, this specific classification is reserved for products whose primary function and formulation are explicitly as caulking agents designed for sealing purposes. The "Other" category would encompass mastics with different primary applications, such as for bonding, filling broader gaps, or specialized industrial uses not primarily focused on sealing.

As this is a leaf node within the HTS structure, there are no further subcategories under 3214.10.00.10. Therefore, the classification is definitive for any product meeting the description of a caulking compound. When classifying, focus on the material's intended use as a sealant and its physical properties that facilitate this function, such as its elasticity, adhesion, and resistance to environmental factors once cured.