HTS code 9902.13.80 covers "Sleeping bag shells, unfilled, of woven taffeta fabric of polyester with thread count between 160 and 210 and formed from yarns between 22 and 112 decitex; such shells each weighing 25 g/m2 or more but not over 250 g/m2; measuring 152 cm to 305 cm in length, with zipper closure, valued not over $7 each (provided for in subheading 6307.90.98) " 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.