HTS tariff line · chapter 29
2921.59.17
4,4'-Benzidine-2,2'-disulfonic acid; 1,4-Diaminobenzene-2-sulfonic acid; 4,4'-Methylene bis ((3-chloro-2,6-diethylaniline); 4,4'-Methylene bis(2,6-diethylaniline); 4,4'-Methylene bis (2,6-diisopropylaniline);m-Xylene diamine; and 3,3'-Diaminobenzidine (tetraaminobiphenyl)
Analysis
HTS 2921.59.17 covers 4,4'-Benzidine-2,2'-disulfonic acid; 1,4-Diaminobenzene-2-sulfonic acid; 4,4'-Methylene bis ((3-chloro-2,6-diethylaniline); 4,4'-Methylene… under heading 2921 (amine-function compounds).
Within this group the rate runs from duty-free to 6.5%. Compared with 2921.59.80 (other: other), which pays 6.5%, a misclassification either way moves the duty by 6.5 percentage points.
The normal trade relations rate here is zero, shared by about 26% of the 1050 tariff lines in chapter 29, a useful check when a neighbouring dutiable line is a candidate. Free here means free of the base duty only: origin-specific Chapter 99 duties such as Section 301 can still be owed.
Census statistics map these goods to NAICS 325194 (Cyclic Crude, Intermediate, and Gum and Wood Chemical Manufacturing), an industry of 68 US establishments employing 5,542 people. That concordance is how imports of this line are compared with US output.
Every edition we compared, from Jan 2023 to Oct 2026 (Rev. 22), shows the same general rate of Free.
Neighbouring lines
| Line | Description | General rate |
|---|---|---|
| 2921.59.04 | 1,8-Diaminonaphthalene (1,8-Naphthalenediamine) | Free |
| 2921.59.08 | 5-Amino-2-(p-aminoanilino) benzenesulfonic acid; 4,4'-Diamino-3-biphenylsulfonic acid (3-Benzidinesulfonic acid); 3,3'-Dimethylbenzidine (o-Tolidine); 3,3'-Dimethylbenzidine hydrochloride; Ethyl-(2-dimethylaminoethyl) aniline;N-Ethyl-N,N'-dimethyl-N'-phenylethylene- diamine; and 4,4'-Methylenebis(2-chloroaniline) | 5.8% |
| 2921.59.20 | 4,4'-Diamino-2,2'-stilbenedisulfonic acid | 6.5% |
| 2921.59.30 | 4,4'-Methylenedianiline | 6.5% |
| 2921.59.40 | Products described in additional U.S. note 3 to section VI | 6.5% |
| 2921.59.80 | Other: other | 6.5% |