Boric Acid Welding Flux Powder from China

Fine powder of boric acid and borates used as flux for oxyacetylene brazing of steel parts. Wholly inorganic composition prevents oxidation during high-heat joining, classified in 3810.90.2000 as auxiliary preparation for soldering/brazing. Common in HVAC repair.

Duty Rate — China → United States

35%

Rate breakdown

9903.03.0110%Except for products described in headings 9903.03.02–9903.03.11, articles the product of any country, as provided for in subdivision (aa) of U.S. note 2 to this subchapter
9903.88.0325%Except as provided in headings 9903.88.13, 9903.88.18, 9903.88.33, 9903.88.34, 9903.88.35, 9903.88.36, 9903.88.37, 9903.88.38, 9903.88.40, 9903.88.41, 9903.88.43, 9903.88.45, 9903.88.46, 9903.88.48, 9903.88.56, 9903.88.64, 9903.88.66, 9903.88.67, 9903.88.68, or 9903.88.69, articles the product of China, as provided for in U.S. note 20(e) to this subchapter and as provided for in the subheadings enumerated in U.S. note 20(f)

Import Tips

Certify boron content <15% water-soluble for non-hazardous shipping

Provide AWS flux classification specs for customs verification

Avoid bulk boric acid declaration; formulation specificity required