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Chlorobutyl Rubber (CIIR) from Germany

Chlorinated isobutylene-isoprene rubber (CIIR) in primary pellet or bale form, where chlorinated monomer units predominate >95% by weight. Widely used in tire inner liners and pharmaceutical stoppers for air impermeability. Classified in 3911.90.70.00 as chlorinated synthetic rubber.

Duty Rate — Germany → United States

10%

Rate breakdown

9903.05.3910%Section 301 (forced labor) — European Union member state (col1 rate < 10 percent): MFN < 10% → total duty capped at 10%

Import Tips

Include monomer weight breakdown certificate to satisfy note (a)(1) 'poly' designation rules

Label as 'primary form' explicitly; compounded versions risk moving to 3926.90

Avoid misdeclaration as regular butyl (4002.31); chlorination shifts to Chapter 39