# HTS 9902.05.40: Tetrakis(hydroxymethyl)phosphonium sulfate (CAS No. 55566-30-8) (provided for in subheading 2931.90.90)

> Plain-language tariff reference from the USITC Harmonized Tariff Schedule on [PlainTariff](https://plaintariff.com/).

## Duty rates

- **General (MFN) rate:** Free
- **Special / FTA rate:** No change
- **Column 2 rate:** No change
- **Corpus rank:** #4812 of 5979 among duty-free tariff lines

## Classification path

- **Section XXII:** [Special Classification Provisions](https://plaintariff.com/section/xxii-special-classification-provisions)
- **HTS code:** 9902.05.40

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*Source: U.S. International Trade Commission Harmonized Tariff Schedule. HTML canonical: https://plaintariff.com/heading/99020540-tetrakishydroxymethylphosphonium-sulfate-cas-no-55566-30*