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2931.49.00.55/Methylphosphonic Acid Monomethyl Ester/Mexico

Methylphosphonic Acid Monomethyl Ester from Mexico

This partial ester (CH3P(O)(OH)(OCH3)) has phosphorus bonded to one methyl group, meeting the HTS 2931.49.0055 specification precisely. The single methoxy group counts as the allowed C1 substituent. Used in specialty polymer flame retardants.

Duty Rate — Mexico → United States

13.7%

Rate breakdown

9903.05.5510%Section 301 (forced labor) — additional 10% ad valorem on products of Mexico
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Import Tips

• Label with exact CAS number (25989-52-0) and IUPAC name for customs verification

• Declare stabilization additives separately to avoid mixture classification issues

Methylphosphonic Acid Monomethyl Ester from Mexico — Import Duty Rate | HTS 2931.49.00.55