Butyl Rubber for Pharmaceutical Stoppers
> Pure isobutene-isoprene (butyl) rubber (IIR) in bale form, optimized for pharmaceutical vial stoppers. It is in primary bulk form (bales) under Chapter Note 3(b) and is not compounded, retaining the essential character of raw synthetic rubber, making it classifiable under tariff item 4002.31.00.
Import Duty Rates by Country of Origin
| Origin Country | MFN Tariff | Surtaxes | Total Effective Rate |
|---|---|---|---|
| 🇨🇳China | Free | — | Free |
| 🇲🇽Mexico | Free | — | Free |
| 🇺🇸United States | Free | — | Free |
| 🇩🇪Germany | Free | — | Free |
| 🇯🇵Japan | Free | — | Free |
More Specific Codes
This product may fall under a more specific subheading:
Alternative Classifications
This product could be classified differently depending on its characteristics or intended use.
If the rubber is molded or cut into finished stopper articles.
Articles of vulcanized rubber are classified in heading 40.16.
If the rubber is compounded with curing agents for stopper production.
Compounded rubber falls under other synthetic rubber headings.
Not sure which classification is right?
The Tariff Assistant works through the GRI rules on your specific product to reach the right tariff item — and can price the duty on it in the same conversation.
Import Tips & Compliance
• > Ensure the bales are free of pigments or fillers, except for identification purposes as per Chapter Note 5(A)(ii)
• Provide documentation that the rubber is uncompounded and meets pharmaceutical-grade specifications
• Be aware that if the rubber is cut to shape for stoppers, it may fall under a different heading
Related Products under Tariff item 4002.31.00
Bayer Butyl NC 229 Rubber Solution
> A solution of isobutene-isoprene (butyl) rubber (IIR) in an organic solvent, used for coating applications. It is in primary form (liquid) as defined in Chapter Note 3(a) and retains the essential character of raw synthetic rubber, with the solvent permitted under Chapter Note 5(B) as an additive that does not alter classification.
Butyl Rubber Dispersion for Dipping
> An aqueous dispersion of isobutene-isoprene (butyl) rubber (IIR) intended for latex dipping processes. As a liquid dispersion, it qualifies as a primary form under Chapter Note 3(a) and is not compounded beyond the permitted additives, retaining its raw synthetic rubber character for heading 40.02.
Butyl Rubber Latex Dispersion
> A liquid dispersion of isobutene-isoprene (butyl) rubber (IIR) in water, used for dipping and coating applications in manufacturing gloves and balloons. It is a primary form (latex) under Chapter Note 3(a) and meets the definition of synthetic rubber in Chapter Note 4, not being compounded with prohibited substances.
Butyl Rubber Powder for Tire Liners
> Fine powder form of isobutene-isoprene (butyl) rubber (IIR) used in tire inner liner compounds, supplied in bulk bags. Powder is a primary form under Chapter Note 3(b), and the product is uncompounded, meeting the synthetic rubber definition in Chapter Note 4.
Butyl VM-613 Granules
> VM-613 grade butyl rubber granules from Lion Elastomers for vibration mounts. Granules are a primary form under Chapter Note 3(b), and the product is uncompounded synthetic rubber (IIR), classifiable under tariff item 4002.31.00.
Exxon Butyl 268 Rubber Bale
> Baled isobutene-isoprene rubber (IIR), grade Butyl 268 from ExxonMobil, suitable for tire inner liners and pharmaceutical stoppers. Bales are a primary bulk form under Chapter Note 3(b), and the rubber is uncompounded, meeting the synthetic rubber definition in Chapter Note 4.