HTS code 9902.10.48 covers "Mixtures containing 88 percent or more by weight of poly[oxy(dimethylsilanediyl)] bis[omega-butoxypoly(oxypropylene)] ether (CAS No. 67762-96-3), 8 percent or less by weight α-butyl-ω-hydroxylpoly(oxypropylene) (CAS No. 9003-13-8) and less than 4 percent by weight silica dimethylsilylate (CAS No. 68611-44-9) (provided for in subheading 3824.90.92) " under the US Harmonized Tariff Schedule. This is the official duty rate charged by US Customs when this product is imported into the United States, sourced directly from the U.S. International Trade Commission and refreshed daily.