Helium-3/Helium-4 Hyperpure Mixture from Japan
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 — Japan → United States
3.7%
Rate breakdown
9903.05.860%Universal product exemption (U.S. note 52(b))
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