Mercaptan Polysulfide Elastomer Base M-100 from Mexico
Mercaptan Polysulfide Elastomer Base M-100 is a low-viscosity primary resin for two-part sealants. Classified in HTS 3911.90.10.00 for elastomeric polysulfides, with thiol groups enabling crosslinking. Primary form ensures it stays in heading 3911, not as finished rubber.
Duty Rate — Mexico → United States
10%
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
• Require supplier declaration of no fittings/attachments to maintain heading 3917 exclusion note applicability
• Test for polymer purity; impurities >5% may reclassify per predominant monomer rule
• Avoid bulk packaging confusion with retail sets that could invoke 3924 household exclusions