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Zircon-Mullite Refractory Block from China

Zircon-mullite refractory blocks are fired ceramic construction blocks blending zircon and mullite for glass furnace crowns and regenerators. They resist alkali corrosion and thermal cycling. HTS 6902.90.50.20 applies to these other refractory ceramic blocks.

Duty Rate — China → United States

37.5%

Rate breakdown

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)
9903.05.3112.5%Section 301 (forced labor) — additional 12.5% ad valorem on products of China

Import Tips

Submit mineralogical analysis to prove inorganic nonmetallic fired composition per Chapter 69 notes

Ensure blocks are not cermets (8113) by confirming no metallic binders

Pair with end-use declarations for furnace construction to prevent reclassification as parts