2921.51.10.00—4-Amino-2-(N,N-diethylamino) toluene hydrochloride;m-Phenylenediamine;o-Phenylenediamine; Toluene-2,4-diamine; Toluene-2,5-diamine; and Toluene-2,5-diamine sulfateGeneral
6.5%
Units
kg
Column 2
15.4¢/kg + 48.5%
Special
Free (A+,AU,BH,CL,CO,D,E,IL,JO,KR,L,MA,OM,P,PA,PE,S,SG)
HTS 2921.51.10.00 is the U.S. Harmonized Tariff Schedule classification for 4-Amino-2-(N,N-diethylamino) toluene hydrochloride;m-Phenylenediamine;o-Phenylenediamine; Toluene-2,4-diamine; Toluene-2,5-diamine; and Toluene-2,5-diamine sulfate. It's a 10-digit statistical line in Chapter 29: Organic chemicals, Section VI: Products of the Chemical or Allied Industries, used by U.S. Customs and Border Protection to determine the duty rate at entry. 1 active AD/CVD order flags this code.
New to HTS codes? Read our guide on how HTS classification works →
Active orders that may apply to imports under this HTS code. HTS coverage is advisory — actual scope depends on each order's product description. Run the AD/CVD lookup → to check whether your specific shipment is in scope.
Past CBP decisions classifying real products under this HTS code. Useful precedent when classifying a similar product — each ruling shows how CBP interpreted the code for a specific case.
The tariff classification of m-phenylenediamine from China
he tariff classification of Indigo Extract; Phenylene Diamine
Source: CBP CROSS (view all rulings on rulings.cbp.gov →)
HTS 2921.51.10.00 is the U.S. Harmonized Tariff Schedule classification for 4-Amino-2-(N,N-diethylamino) toluene hydrochloride;m-Phenylenediamine;o-Phenylenediamine; Toluene-2,4-diamine; Toluene-2,5-diamine; and Toluene-2,5-diamine sulfate. It belongs to Chapter 29 of the HTSUS.
The general (Column 1) duty rate for HTS 2921.51.10.00 is 6.5%. This is the most-favored-nation (MFN) rate that applies to imports from World Trade Organization member countries.
Yes. Imports of HTS 2921.51.10.00 from countries party to a trade program (such as USMCA, KORUS, GSP, or the African Growth and Opportunity Act) may qualify for the special rate: Free (A+,AU,BH,CL,CO,D,E,IL,JO,KR,L,MA,OM,P,PA,PE,S,SG). Eligibility depends on rules of origin and certification.
The Column 2 rate for HTS 2921.51.10.00 is 15.4¢/kg + 48.5%. 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 2921.51.10.00 in Tandom's catalog. Use the calculator's date + origin inputs to confirm against any retroactive overlay you may be filing.
Yes — 1 AD/CVD order flag this code: A-533-847 (AD, India). Open the code page for deposit rates, scope determinations, and the linked case lookups.
Free Trade Agreement and special-program eligibility
Tandom guides relevant to this code
Where trade compliance APIs fit in a broker's filing pipeline: HTS classification, duty calculation, AD/CVD scope match, and post-summary corrections.
Open resource
Cash deposit cascade, separate rates, all-others, and PRC-wide rates. Worked example on case A-570-910 (galvanized welded steel pipe from China) with three exporter-specific rates.
Open resource
Scope text is authoritative; the HTS list is illustrative. Read scope, find past rulings, and file a 19 CFR 351.225 inquiry. Worked example on case A-570-106 (wooden cabinets from China).
Open resource
Run thousands of product descriptions through HTS classification, score the confidence, and triage borderline rows. Public search endpoint plus the closed-beta three-layer Classifier.
Open resource
How to read, order, and report Chapter 99 HTS codes alongside the base classification on a US entry summary in 2026. The full stacking ladder for brokers and compliance teams.
Open resource
Why raw LLM prompts fabricate stat suffixes, why MCP-augmented prompts do not, and the prompt template a broker can hand to Claude or ChatGPT today.
Open resource