HTS code 4502.00.00.00 covers "Natural cork, debacked or roughly squared, or in rectangular (including square) blocks, plates, sheets or strip (including sharp-edged blanks for corks or stoppers)" 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.