HTS code 7304.59.20 covers "Tubes, pipes and hollow profiles, seamless, of iron (other than cast iron) or steel › Other › Suitable for use in the manufacture of ball or roller bearings › Suitable for use in boilers, superheaters, heat exchangers, condensers, refining furnaces and feedwater heaters" 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.