Analysis
Subheading 8547.10 covers insulating fittings of ceramics, within heading 8547. The first six digits are shared by every country that uses the Harmonized System, so this part of the code is the same in the US, UK and EU schedules; the 2 US tariff lines below it are national.
None of its 2 lines is duty-free at the general rate. Rates run from 3% to 3% with a median of 3%, so the line you choose sets the duty.
The US splits it as follows: 8547.10.40 for ceramic insulators to be used in the production of spark plugs for… (3%) and 8547.10.80 for insulating fittings of ceramics: other (3%).
By Census's concordance, most of its statistical lines are made by Pottery, Ceramics, and Plumbing Fixture Manufacturing (327110). Those are the NAICS industries a US producer of these goods would report under.
Goods only reach 8547.10 once they fall within heading 8547 (insulating fittings for electrical machines, appliances or equipment, being fittings…). Under General Rule 6, subheadings are then compared only with others at the same level, so a product is matched against its siblings, not against lines elsewhere in the chapter.
Tariff lines
| Line | Description | General rate |
|---|---|---|
| 8547.10.40 | Ceramic insulators to be used in the production of spark plugs for natural gas-fueled, stationary, internal combustion engines | 3% |
| 8547.10.80 | Insulating fittings of ceramics: other | 3% |