HTS code 9902.14.71 covers "Catalytic converter needled blanket mats of ceramic fibers, containing over 65 percent by weight of aluminum oxide and not over 3 percent by weight of acrylic latex organic binder, of a basis weight less than 1745 g/m2, measuring 5.0 mm or more but not over 9.9 mm in thickness; presented in bulk, sheets or rolls, designed for use in motor vehicles of heading 8703 (provided for in subheading 6806.10.00). " 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.