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Tributylphosphine from Mexico

Tributylphosphine (PBu3) is a tertiary phosphine with three butyl groups attached to phosphorus, used in organic synthesis and catalysis. Classified under HTS 2931.49.00 as a non-halogenated organo-phosphorus derivative among other organo-inorganic compounds. Its air-sensitive nature requires stabilizer additions permitted by Chapter 29 note (f).

Duty Rate — Mexico → United States

13.7%

Rate breakdown

9903.05.5510%Except for products described in headings 9903.05.85–9903.05.92 and 9903.05.94, articles the product of Mexico, as provided for in U.S. note 52 to this subchapter

Import Tips

• Include stabilizer certificates if added for preservation, as allowed under Chapter 29 note (f)

• Label as UN 3254 for phosphine pyrophoric liquid classification during transport

• Avoid classification pitfalls by confirming no sulfur or metal-carbon bonds per heading 2930/2931 exclusions