U.S. exports of parts of cathode tubes (nesoi) (HS 854099) totaled $3.3M in August 2026.
Importers of Parts of Cathode Tubes (NESOI) paid $166K in duties in August 2026, an effective tariff rate of 11.23% of the $1.5M imported — duty actually collected as a share of that value, not the published tariff schedule. Parts of Cathode Tubes (NESOI) imports of $1.5M in August 2026 ran 28% below the year-to-date monthly average of $2.0M.
Last updated: August 2026 dataElectron guns (8540994000) and RF interaction structures for microwave tubes sit alongside general thermionic, cold-cathode, and photocathode tube parts (8540990000 and 8540998000) under this heading — a mix that serves defense electronics, scientific instrumentation, and legacy broadcast equipment. Czech Republic and Japan are the leading US suppliers, reflecting specialized manufacturing capabilities concentrated in Europe and East Asia. Importers should verify whether specific parts fall under Export Control Classification Numbers, as many cathode-tube components intersect with dual-use technology regulations.
AI-written summary of the official U.S. Census Bureau trade figures on this page — verify before relying on it.
82 shipments/mo
The US schedule separates electron guns and RF interaction structures for microwave tubes (8540994000) from general thermionic, cold-cathode, and photocathode tube parts. The residual NESOI lines (8540990000 and 8540998000) capture parts not specifically described elsewhere; classification often turns on whether the part is dedicated to a microwave tube function or to a broader thermionic/cold-cathode application.
Parts under 854099 are not broadly subject to Section 301 List tariffs in the same way as many consumer electronics, but importers should confirm the current status of each 10-digit line, as trade-remedy applicability can change. Dual-use export-control screening is also advisable for electron guns and microwave interaction structures.
HSChapter 85
Subheading 6 of 11 in heading 8540
Subheading 854099 · $3.3M of $42.4M
Trade Directory
List your company under HS 854099 — Parts of Cathode Tubes (NESOI), so the companies trading it can find you. Be the first supplier listed.
HS10 import codes under this HS6 parent, each with its own page. Source: U.S. Harmonized Tariff Schedule.
| Code | Description | Import Value | Effective Tariff % | Dutiable Share | Duty Collected |
|---|---|---|---|---|---|
| 8540998000 | Thermionic, Cold/Photo Cathode Tube Parts, NESOI | $1.0M | 11.12% | 92.91% | $115K |
| 8540994000 | Electron Guns, Rf Intraction Struct Fr Microwave | $436K | 11.50% | 84.69% | $50K |
HS10 export codes under this HS6 parent, each with its own page. Source: U.S. Schedule B export classification.
| Code | Description | Export Value |
|---|---|---|
| 8540990000 | Thermionic,Cold Cathode,Phtcathode Tube Parts, Nes | $3.3M |
Import lines come from the U.S. Harmonized Tariff Schedule and export lines from Schedule B. The two are numbered by different agencies, so the same 10-digit code can appear in both tables describing a different product.
ImportsExports
Imports
$1.5MYoY · free account
Exports
$3.3MYoY · free account
12-mo low · imports
YoY · free accountOver the twelve months to August 2026, the U.S. imported $25.1M of Parts of Cathode Tubes (NESOI).
Through August 2026. Source: U.S. Census Bureau.
Exports · August 2026
destination
Korea, South and Singapore together take 50% of it.
customs district
origin
entry
rate provision · imports
6.0% enters free of duty; duty collected equals 11.23% of total import value.