Description: 3,9-Dimethyl-2,4,8,10-tetraoxa-3,9-diphosphaspiro [5.5] undecane 3,9-dioxide
Base HTS fields include an official source, retrieval date, and calculation trace. This page still remains a planning and broker-review prep page.
US import duty quick answer
HS 2931.48.00.00 (3,9-Dimethyl-2,4,8,10-tetraoxa-3,9-diphosphaspiro [5.5] undecane...) has a source-backed MFN base rate of 3.7%. For China-origin shipments, Section 301, Section 122, Section 232, AD/CVD, and exclusions must be reviewed as separate layers; this page does not present unsupported layers as a final filing rate.
HTS code
2931.48.00.00
Base MFN rate
3.7%
Planning view
Base 3.7% + review layers
MFN base duty
3.7%From the USITC HTS general/base duty field.
Section 301 / Chapter 99
Review requiredThis page does not have enough public source evidence to publish this layer. Review USTR lists, Chapter 99 instructions, and exclusions separately.
Section 122 / temporary baseline
Current-status reviewTemporary or litigated tariff layers should be verified against current Federal Register, CBP, and broker guidance before they are added to the base rate.
Section 232 / product-specific remedies
Product reviewSection 232 is not a default layer outside sensitive products such as steel, aluminum, copper, autos, and lumber, but product and Chapter 99 review still matter.
China-origin planning view
Base 3.7% + review layersTreat this as a public composite only when every component has a complete source chain.
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Set up a tariff change watchHS 2931.48.00.00 is the HTS line for 3,9-Dimethyl-2,4,8,10-tetraoxa-3,9-diphosphaspiro [5.5] undecane 3,9-dioxide. The base duty comes from the USITC HTS source field; final filing still depends on product specs, origin, special programs, Chapter 99, and broker review.
Description
3,9-Dimethyl-2,4,8,10-tetraoxa-3,9-diphosphaspiro [5.5] undecane 3,9-dioxide
Data source and update date
Base source: USITC HTS revision feed. Retrieved: 2026-07-20; version: 2026-revision-11.
This page does not have enough public source evidence to publish this layer. Review USTR lists, Chapter 99 instructions, and exclusions separately.
The same HS code can produce very different planning outcomes by origin. This table compares scenarios; it is not a final filing determination.
| Origin | MFN | Section 301 | Section 122 | Section 232 | Planning view | Note | Compare in calculator |
|---|---|---|---|---|---|---|---|
| China | 3.7% | Review required | Current-status review | Product review | Base 3.7% + review layers | Highest need for Section 301, Chapter 99, exclusions, and AD/CVD review. | Compare in calculator → |
| Vietnam | 3.7% | Usually not applicable | Current-status review | Product review | Base 3.7% + current temporary-layer review | Useful alternative-origin scenario; still verify temporary layers, origin, and product-specific measures. | Compare in calculator → |
| Mexico (USMCA) | Preferential if qualified | Usually not applicable | Check USMCA qualification | Product review | Potentially 0% if USMCA-qualified | Requires origin and USMCA documentation; transshipment is not origin transformation. | Compare in calculator → |
| India | 3.7% | Usually not applicable | Current-status review | Product review | Base 3.7% + current temporary-layer review | Good sourcing-alternative scenario; still verify by product and entry date. | Compare in calculator → |
This section only publishes base HTS information with source fields attached. Base HTS and additional-duty review work stay separate so the page does not overstate unsupported composite estimates.
HTS general rate field: 3.7%
Rate-output note: only the base HTS field is shown here. Additional duties, Chapter 99 treatment, exclusions, or AD/CVD still require separate review.
Calculation method
Exact official field
Source name
USITC HTS revision feed
Retrieved date
2026-07-20
Effective date
-
Version / revision
2026-revision-11
Confidence status
official-source
Review status
Verified
The public page separates base HTS, additional layers, and public visibility. Dashed bars show a component may exist in the planning stack but is not yet source-complete enough to publish as a public rate.
Base HTS
Exact official field
IEEPA / additional tariff layer
No source-backed public policy document is attached to this component yet, so the rate is hidden.
Section 301 / Chapter 99 layer
No source-backed public policy document is attached to this component yet, so the rate is hidden.
Base-field precision
94%Exact official field
Source freshness
88%Inside freshness window
Public visibility
22%Still review-gated
Treat the following items as a broker/compliance review checklist, not as an automated determination. The core checks are Chapter 99, Section 301, USTR exclusions, AD/CVD, quotas or safeguards, and broker confirmation.
The entered code (2931.48.00.00) is specific enough to start a rate review, but classification still requires product facts and broker/official confirmation.
Open USITC HTS searchUse the product description when comparing material, construction, principal use, and classification rationale from rulings.
Search CBP CROSSCandidate 2931.48.00.00: 3,9-Dimethyl-2,4,8,10-tetraoxa-3,9-diphosphaspiro [5.5] undecane 3,9-dioxide. General duty field: 3.7%.
Open USITC HTS searchTariffsChart can apply 3.7% as a planning base duty rate. Still verify special rates, units, footnotes, and applicability.
For China-origin goods, verify Section 301 coverage, exclusions, IEEPA/other current trade-remedy FAQs, and any required Chapter 99 secondary classifications. The automated result does not determine coverage.
Open CBP Section 301 FAQSearch ACCESS/AD-CVD by country, product, commodity, case number, and HTS. Scope language controls; an HTS match is only a screening signal.
Open AD/CVD SearchVerified HTS detail pages from the same heading or chapter. Use them to compare adjacent classifications, materials, and use cases before broker review.
Source retrieved: 2026-07-20
Source retrieved: 2026-07-20
Source retrieved: 2026-07-20
Source retrieved: 2026-07-20
Source retrieved: 2026-07-20
Source retrieved: 2026-07-20
Source retrieved: 2026-07-20
Source retrieved: 2026-07-20
Source retrieved: 2026-07-20
Source retrieved: 2026-07-20
Source retrieved: 2026-07-20
Source retrieved: 2026-07-20
These are the official-source entry points this route should open and preserve before relying on any shipment assumption.
official-source · 2026-07-27
Candidate HTS: 2931.48.00.00 Description: 3,9-Dimethyl-2,4,8,10-tetraoxa-3,9-diphosphaspiro [5.5] undecane 3,9-dioxide General rate field: 3.7% Simple ad-valorem rate parsed for planning: 3.7%
Open official sourceofficial-source · 2026-07-27
Search for binding CBP rulings involving similar merchandise. Capture ruling number, date, product facts, classification rationale, and whether the facts match this SKU. CROSS examples help frame broker questions but do not automatically classify your product.
Open official sourceofficial-source · 2026-07-27
For China-origin goods, verify whether the HTS classification is covered by Section 301 remedies, whether any exclusion applies, and which Chapter 99 secondary classification should be reported. Do not infer coverage from the base HTS line alone.
Open official sourceofficial-source · 2026-07-27
Check USTR Section 301 tariff actions, exclusion notices, and extension status. Save the specific list/exclusion evidence if a product exclusion is claimed.
Open official sourceofficial-source · 2026-07-27
Search Commerce ACCESS/AD-CVD resources by country, product, case number, HTS number, and commodity. AD/CVD scope can be broader or narrower than an exact HTS match; ask the broker whether a scope ruling or specialist review is needed.
Open official sourceofficial-source · 2026-07-27
Review whether any current CBP trade-remedy FAQ, CSMS message, or Chapter 99 note applies in addition to Section 301, base duty, AD/CVD, or other measures. This is a prompt for professional review, not an automated determination.
Open official source