HTS code 9902.13.04 covers "Acrylic filament tow containing 85 percent or more by weight of acrylonitrile units and 2 percent or more but not more than 8 percent of water, dyed, such tow with a decitex of 5.0 to 5.6, an aggregate filament measure in the tow bundle between 660,000 and 1,200,000 and a length greater than 2 m (provided for in subheading 5501.30.00) " 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.