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Isobutylene Research Grade from China

Ultra-high purity isobutylene (>99.99%) for laboratory and pharmaceutical synthesis, classified under HTS 2901.23.00.00 as a butene isomer.

Duty Rate — China → United States

37.5%

Rate breakdown

9903.88.0325%Except as provided in headings 9903.88.13, 9903.88.18, 9903.88.33, 9903.88.34, 9903.88.35, 9903.88.36, 9903.88.37, 9903.88.38, 9903.88.40, 9903.88.41, 9903.88.43, 9903.88.45, 9903.88.46, 9903.88.48, 9903.88.56, 9903.88.64, 9903.88.66, 9903.88.67, 9903.88.68, or 9903.88.69, articles the product of China, as provided for in U.S. note 20(e) to this subchapter and as provided for in the subheadings enumerated in U.S. note 20(f)
9903.05.3112.5%Section 301 (forced labor) — additional 12.5% ad valorem on products of China

Import Tips

Include lot-specific purity certificates from accredited labs

Small cylinder shipments require special academic/research import permits

Distinguish from fuel-grade isobutylene to avoid Chapter 27/38 classifications