Tandom · Duty calculator
HTS 6907.21.90.51 is the U.S. Harmonized Tariff Schedule classification for Of a water absorption coefficient by weight not exceeding 0.5%, other. It's a 10-digit statistical line in Chapter 69: Ceramic products, Section XIII: Articles of Stone, Plaster, Cement, Asbestos, Mica or Similar Materials; Ceramic Products; Glass and Glassware, used by U.S. Customs and Border Protection to determine the duty rate at entry. 3 active AD/CVD orders flag this code.
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Active orders that may apply to imports under this HTS code. HTS coverage is advisory — actual scope depends on each order's product description. Run the AD/CVD lookup → to check whether your specific shipment is in scope.
HTS 6907.21.90.51 is the U.S. Harmonized Tariff Schedule classification for Of a water absorption coefficient by weight not exceeding 0.5%, other. It belongs to Chapter 69 of the HTSUS.
The general (Column 1) duty rate for HTS 6907.21.90.51 is 8.5%. This is the most-favored-nation (MFN) rate that applies to imports from World Trade Organization member countries.
Yes. Imports of HTS 6907.21.90.51 from countries party to a trade program (such as USMCA, KORUS, GSP, or the African Growth and Opportunity Act) may qualify for the special rate: Free (AU,BH,CL,CO,D,E,IL,JO,KR,MA,OM,P,PA,PE,S,SG). Eligibility depends on rules of origin and certification.
The Column 2 rate for HTS 6907.21.90.51 is 55%. This rate applies to imports from countries that do not have normal trade relations with the United States (currently Cuba and North Korea).
No active Chapter 99 tariff overlays (Section 301, Section 232, IEEPA reciprocal, etc.) currently flag HTS 6907.21.90.51 in Tandom's catalog. Use the calculator's date + origin inputs to confirm against any retroactive overlay you may be filing.
Yes — 3 AD/CVD orders flag this code: A-570-108 (AD, China), C-570-109 (CVD, China), C-533-929 (CVD, India). Open the code page for deposit rates, scope determinations, and the linked case lookups.
Free Trade Agreement and special-program eligibility
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