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Isobutylene Research Grade from Japan

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

Duty Rate — Japan → United States

12.5%

Rate breakdown

9903.05.4912.5%Section 301 (forced labor) — Japan (col1 rate < 12.5 percent): MFN < 12.5% → total duty capped at 12.5%

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