Trimethyl Phosphite Stabilized with MEHQ from Mexico
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 — Mexico → United States
13.7%
Rate breakdown
9903.05.5510%Section 301 (forced labor) — additional 10% ad valorem on products of Mexico
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%