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Boric Acid Welding Flux Powder from Mexico

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 — Mexico → United States

10%

Rate breakdown

9903.05.5510%Section 301 (forced labor) — additional 10% ad valorem on products of Mexico

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