Analysis
HTS 4504.10.20 covers insulation, coated or not coated, of compressed cork under heading 4504 (agglomerated cork (with or without a binding substance) and articles of agglomerated cork).
Goods classified here enter the United States duty-free at the general (normal trade relations) rate, as do about 95% of the 19 tariff lines in chapter 45. Duty-free at the general rate does not rule out additional duties under Chapter 99, such as Section 301 or Section 232 measures, which depend on the country of origin.
Census statistics map these goods to NAICS 321999 (All Other Miscellaneous Wood Product Manufacturing), an industry of 2,327 US establishments employing 31,381 people. That is the industry code a US manufacturer of the same product would normally use.
All 6 neighbouring lines carry the same duty-free rate, so a borderline choice between them changes the statistics reported, not the duty paid.
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 |
|---|---|---|
| 4504.10.10 | Vulcanized sheets and slabs wholly of ground or pulverized cork and rubber | Free |
| 4504.10.30 | Blocks, plates, sheets and strip; tiles of any shape; solid cylinders, including disks: floor coverings | Free |
| 4504.10.40 | Wallcoverings, backed with paper or otherwise reinforced | Free |
| 4504.10.45 | Stoppers, not tapered, wholly of cork, of a thickness (or length) greater than the maximum diameter | Free |
| 4504.10.47 | Corks, stoppers, disks, wafers and washers: other | Free |
| 4504.10.50 | Blocks, plates, sheets and strip; tiles of any shape; solid cylinders, including disks: other | Free |