Tandom · Duty calculator
Add country and invoice value for the full duty stack — base + 301 + 232 + AD/CVD + fees.
HTS 4002.31.00.00 is the U.S. Harmonized Tariff Schedule classification for Isobutene-isoprene (butyl) rubber (IIR). It's a 10-digit statistical line in Chapter 40: Rubber and articles thereof, Section VII: Plastics and Articles Thereof; Rubber and Articles Thereof, used by U.S. Customs and Border Protection to determine the duty rate at entry. No Chapter 99 tariff modifications (Section 301, Section 232, IEEPA) or AD/CVD orders currently flag this code in Tandom's catalog.
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HTS 4002.31.00.00 is the U.S. Harmonized Tariff Schedule classification for Isobutene-isoprene (butyl) rubber (IIR). It belongs to Chapter 40 of the HTSUS.
The general (Column 1) duty rate for HTS 4002.31.00.00 is Free. This is the most-favored-nation (MFN) rate that applies to imports from World Trade Organization member countries.
The Column 2 rate for HTS 4002.31.00.00 is 20%. This rate applies to imports from countries that do not have normal trade relations with the United States (currently Cuba and North Korea).
No active Chapter 99 tariff overlays (Section 301, Section 232, IEEPA reciprocal, etc.) currently flag HTS 4002.31.00.00 in Tandom's catalog. Use the calculator's date + origin inputs to confirm against any retroactive overlay you may be filing.
No active AD/CVD orders currently flag HTS 4002.31.00.00 in Tandom's catalog. Tandom monitors Federal Register notices daily; a flag will appear here within 24h of any new order's publication.
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