Helium-3/Helium-4 Hyperpure Mixture from Mexico
Hyperpure helium mixture with He-3 isotopically enriched to >99% of helium content, meeting HTS 2804.29.0030 for isotopically pure rare gases. Used in dilution refrigerators for ultra-low temperature physics.
Duty Rate — Mexico → United States
3.7%
Rate breakdown
9903.03.030%Articles the product of any country, as provided for in subdivision (aa)(ii) of U.S. note 2 to this subchapter
Import Tips
• Specify He-3 fraction relative to total helium content in certificate of analysis
• Use cryogenic transport containers; declare low-temperature hazard class
• Differentiate from LNG helium mixtures which use different energy headings