# HS code 3810.90: Pickling preparations for metal surfaces; fluxes and other auxiliary preparations for soldering, brazing or welding; soldering, brazing or welding powders and pastes consisting of metal and other materials; preparations of a kind used as cores or coatings for welding electrodes or rods

> HS code 3810.90 covers pickling preparations for metal surfaces; fluxes and other auxiliary preparations for soldering, brazing or welding; soldering, brazing or welding powders and pastes consisting of metal and other materials; preparations of a kind used as cores or coatings for welding electrodes or rods, other than those classified in 3810.10. It sits in heading 38.10 (pickling preparations for metal surfaces; fluxes and other auxiliary preparations for soldering, brazing or welding; soldering, brazing or welding powders and pastes consisting of metal and other materials; preparations of a kind used as cores or coatings for welding electrodes or rods) in chapter 38 (miscellaneous chemical products). Other goods of heading 38.10 are classified under 3810.10 (pickling preparations for metal surfaces; soldering, brazing or welding powders or pastes consisting of metal and other materials). National tariff lines under 3810.90 are live on border.bot for the United States (3 lines, also used by 1 other country).

Source: https://border.bot/hs-codes/381090
Last updated: 11 October 2026

[HS codes](https://border.bot/hs-codes) / [Chapter 38](https://border.bot/hs-codes/38) / [38.10](https://border.bot/hs-codes/3810) / [3810.90](https://border.bot/hs-codes/381090)

## Key facts

- HS code: 3810.90
- Covers: Pickling preparations for metal surfaces; fluxes and other auxiliary preparations for soldering, brazing or welding; soldering, brazing or welding powders and pastes consisting of metal and other materials; preparations of a kind used as cores or coatings for welding electrodes or rods
- Heading: [38.10: Pickling preparations for metal surfaces; fluxes and other auxiliary preparations for soldering, brazing or welding; soldering, brazing or welding powders and pastes consisting of metal and other materials; preparations of a kind used as cores or coatings for welding electrodes or rods](https://border.bot/hs-codes/3810)
- Chapter: [38: Miscellaneous chemical products](https://border.bot/hs-codes/38)
- Edition: HS2022
- Duty in the United States: [See its 3 lines](https://border.bot/countries/united-states/hs-codes/381090)

## What this code covers

HS code 3810.90 covers pickling preparations for metal surfaces; fluxes and other auxiliary preparations for soldering, brazing or welding; soldering, brazing or welding powders and pastes consisting of metal and other materials; preparations of a kind used as cores or coatings for welding electrodes or rods, other than those classified in 3810.10.

The legal text of the subheading is “Other”, in HS2022.

## What it doesn’t cover

Other goods of heading 38.10 are classified under 3810.10 (pickling preparations for metal surfaces; soldering, brazing or welding powders or pastes consisting of metal and other materials).

- [3810.10](https://border.bot/hs-codes/381010) Pickling preparations for metal surfaces; soldering, brazing or welding powders and pastes consisting of metal and other materials

## How it is structured

3810.90 is a six-digit subheading. Its first two digits, 38, are the chapter; the first four, 3810, are heading 38.10; the last two, 90, identify the subheading within the heading.

Countries add their own digits after these six for their national tariff lines.

- Chapter 38: Miscellaneous chemical products
- Heading 38.10: Pickling preparations for metal surfaces; fluxes and other auxiliary preparations for soldering, brazing or welding; soldering, brazing or welding powders and pastes consisting of metal and other materials; preparations of a kind used as cores or coatings for welding electrodes or rods
- Subheading 3810.90: Other

## In other countries

National tariff lines under 3810.90 are live on border.bot for the United States (3 lines, also used by 1 other country).

- [United States](https://border.bot/countries/united-states/hs-codes/381090): 3 lines, used by 1 other country

- Previous subheading: [3810.10](https://border.bot/hs-codes/381010) Pickling preparations for metal surfaces; soldering, brazing or welding powders and pastes consisting of metal and other materials
- Next subheading: [3811.11](https://border.bot/hs-codes/381111) Anti-knock preparations: Based on lead compounds

## Frequently asked questions

### What does HS code 3810.90 cover?

HS code 3810.90 covers pickling preparations for metal surfaces; fluxes and other auxiliary preparations for soldering, brazing or welding; soldering, brazing or welding powders and pastes consisting of metal and other materials; preparations of a kind used as cores or coatings for welding electrodes or rods, other than those classified in 3810.10.

### Which heading and chapter is HS code 3810.90 in?

HS code 3810.90 is in heading 38.10 (pickling preparations for metal surfaces; fluxes and other auxiliary preparations for soldering, brazing or welding; soldering, brazing or welding powders and pastes consisting of metal and other materials; preparations of a kind used as cores or coatings for welding electrodes or rods) in chapter 38 (miscellaneous chemical products).

### Where are goods of heading 38.10 classified when 3810.90 doesn’t fit?

Other goods of heading 38.10 are classified under 3810.10 (pickling preparations for metal surfaces; soldering, brazing or welding powders or pastes consisting of metal and other materials).

### Which countries’ tariffs list national lines under HS code 3810.90?

National tariff lines under 3810.90 are live on border.bot for the United States (3 lines, also used by 1 other country).

## Sources and updates

The Harmonized System legal text comes from border.bot release 2 (edition HS 2022), imported from a file, and has been live since 11 October 2026.

This page was last updated on 11 October 2026.

Guidance from published tariff data, not a binding ruling. For a decision customs must follow, apply to the destination’s customs authority for a binding tariff ruling.

Machine-readable: https://border.bot/hs-codes/381090.json