Trimethyl Phosphite Stabilized with MEHQ from Canada
P(OCH3)3 with phosphorus bearing three methyl groups via oxygen links, but classified by the single methyl characteristic in HTS 2931.49.0055 per chapter notes allowing stabilizers. The MEHQ inhibitor doesn't affect principal classification. Polymerization inhibitor.
Duty Rate — Canada → United States
100%
Rate breakdown
9903.04.6096.3%Pharmaceuticals Annex IV: patented pharma articles — 100% floor rate
9903.05.900%Articles already subject to Section 232 (steel/aluminum/copper + derivatives, autos + parts, wood, medium/heavy vehicles + parts, semiconductors, patented pharma) — U.S. note 52(f)
Import Tips
• Declare stabilizer percentage (<0.1% MEHQ); note 2(g) allows without reclassification
• Air-reactive; requires inert atmosphere packaging and UN2789 shipping papers
• Distinguish from pesticide phosphites (3808) via purity certificate >99%