U.S. Customs and Border Protection · CROSS Database · 2 HTS codes referenced
Primary HTS Code
8421.21.0000
$155.6M monthly imports
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Court Cases
2 cases
CIT & Federal Circuit
Ruling Age
32 years
Data compiled from CBP CROSS Rulings, Census Bureau Trade Data, CourtListener (CIT/CAFC) · As of 2026-04-30 · Updates monthly
The tariff classification of water and fuel treatment units from Spain
NY 894074 February 7, 1994 CLA-2-84:S:N:N1:105 894074 CATEGORY: Classification TARIFF NO.: 8421.21.0000; 8421.29.0060 Mr. Jose M. Goyanes Globe Limited, Inc. 1300 Coral Way, Suite 301 Miami, Florida 33145 RE: The tariff classification of water and fuel treatment units from Spain Dear Mr. Goyanes: In your letter dated December 27, 1993 you requested a tariff classification ruling. The water treatment unit is a hollow cylindral shape containing three magnets, iron, neodymium and H-53 boron, encapsulated in hydro-tetra-fluoride located in an exterior covering of the cylinder made of Mu-metal. It is installed to the piping in a water supply system. Calcium and magnesium particles suspended in the water supply are exposed to magnetic fields generated by the inductors which causes an electronic structure change that prevents them from bonding to the pipe walls and other parts of the water system. The fuel treatment unit is the same as the water treatment unit in both make-up and function, except smaller in size. It is attached to the fuel line of combustion engines. The unit prevents resins, detergents and other corrosive deposits from bonding to the various parts of the motor and fuel line by causing an electronic structure change in these particles suspended in the hydrocarbon fuel. The applicable subheading for the water treatment unit will be 8421.21.0000, Harmonized Tariff Schedule of the United States (HTS), which provides for filtering or purifying machinery and apparatus for liquids: for filtering or purifying water. The rate of duty will be 3.9 percent ad valorem. The applicable subheading for the fuel treatment unit will be 8421.29.0060, HTS, which provides for other filtering or purifying machinery and apparatus for liquids, other. The rate of duty will be 3.9 percent ad valorem. This ruling is being issued under the provisions of Section 177 of the Customs Regulations (19 C.F.R. 177). A copy of this ruling letter should be attached to the entry documents filed at the time this merchandise is imported. If the documents have been filed without a copy, this ruling should be brought to the attention of the Customs officer handling the transaction. Sincerely, Jean F. Maguire Area Director New York Seaport