💾 Data Updated: Latest version • Last updated: December 09, 2025

4002.31.00.00 - Isobutene-isoprene (butyl) rubber (IIR) 🖩

Details

FieldValue
Unit of Quantitykg
General Rate of Duty (Column 1 - General)Free
Special Rate of Duty (Column 1 - Special)N/A
Column 2 Rate of Duty20%
Quota QuantityN/A
Additional DutiesN/A
About Duty Rates: Rates are divided into Column 1 and Column 2. Column 1 is subdivided into General (normal trade relations rates for all countries not eligible for special programs) and Special (preferential rates for countries with free trade agreements or preference programs). Column 2 rates apply to products from Cuba, North Korea, Belarus, and Russia. When no special rate exists for a classification, General rates apply.

Overview

This HTS category specifically covers isobutene-isoprene (butyl) rubber, commonly known as IIR. This synthetic rubber is characterized by its low gas permeability and excellent resistance to heat, ozone, and weathering. It is typically supplied in its primary forms, such as bales, or in plates, sheets, or strip. IIR is widely used in applications requiring airtightness, such as inner tubes for tires, seals, gaskets, and pharmaceutical stoppers.

The distinguishing factor for this category, 4002.31.00.00, lies in its precise identification of isobutene-isoprene (butyl) rubber. It differentiates itself from its sibling category, 4002.39.00.00, which encompasses "Other" synthetic rubbers and factice derived from oils, not otherwise specified in heading 4002. This means that while both fall under the broader classification of synthetic rubber, 4002.31.00.00 is exclusively for IIR.

As this is a leaf node within the HTS, there are no further subcategories to introduce. Classification within this heading relies on the specific identification of the material as isobutene-isoprene (butyl) rubber (IIR). Therefore, to correctly classify goods under 4002.31.00.00, importers and exporters must confirm that the product is indeed IIR and not another type of synthetic rubber.

Frequently Asked Questions

›What is HTS code 4002.31.00.00?
HTS code 4002.31.00.00 covers Isobutene-isoprene (butyl) rubber (IIR) under the US Harmonized Tariff Schedule. It falls under Chapter 40: Rubber and articles thereof.
›What products are classified under 4002.31.00.00?
This classification covers Isobutene-isoprene (butyl) rubber (IIR). It is a subcategory of Isobutene-isoprene (butyl) rubber (IIR); halo-isobutene-isoprene rubber (CIIR or BIIR):.
›What is the import duty rate for 4002.31.00.00?
The general rate of duty for HTS 4002.31.00.00 is Free. The Column 2 rate is 20%.
›What unit of quantity is used for 4002.31.00.00?
Imports under HTS 4002.31.00.00 are measured in kg.

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