Mica RF Window Disks
Mica RF window disks are circular pieces of worked mica that are transparent to radio frequencies, used in high-power RF transmitters as vacuum windows. They are made from high-quality muscovite mica, carefully cleaved and shaped. These disks are classified under tariff item 6814.90.00 as articles of worked mica.
Import Duty Rates by Country of Origin
| Origin Country | MFN Tariff | Surtaxes | Total Effective Rate |
|---|---|---|---|
| 🇨🇳China | Free | — | Free |
| 🇲🇽Mexico | Free | — | Free |
| 🇺🇸United States | Free | — | Free |
| 🇩🇪Germany | Free | — | Free |
| 🇯🇵Japan | Free | — | Free |
Alternative Classifications
This product could be classified differently depending on its characteristics or intended use.
If the disks are fitted with metal flanges or are part of an electrical fitting.
Fittings of insulating material are classified under heading 85.47.
Not sure which classification is right?
The Tariff Assistant works through the GRI rules on your specific product to reach the right tariff item — and can price the duty on it in the same conversation.
Import Tips & Compliance
• Ensure the disks are not considered parts of electrical apparatus, which could shift classification to Chapter 85
• Provide documentation on the mica grade and manufacturing process
• Verify if any export permits are needed for the mica source, as CBSA may require proof of origin
Related Products under Tariff item 6814.90.00
Agglomerated Mica Heating Element Plates
Agglomerated mica heating element plates are manufactured by bonding reconstituted mica with heat-resistant binders, then pressing them into flat plates. These plates are designed to support heating wires in electric heaters and toasters, where they provide electrical insulation and thermal stability. They fall under tariff item 6814.90.00 as articles of agglomerated mica, not elsewhere specified.
Agglomerated Mica Kiln Shelves
Agglomerated mica kiln shelves are large, flat panels made from reconstituted mica bonded with inorganic binders, capable of withstanding temperatures up to 1000°C. They are used in kilns to support pottery and ceramics during firing. These shelves are classified under tariff item 6814.90.00 as other articles of agglomerated mica.
Mica Electrical Insulation Sheets
Mica electrical insulation sheets are thin, flexible sheets made from worked mica, either split or cleaved, used to insulate electrical components in motors and transformers. They provide high dielectric strength and heat resistance. These sheets fall under tariff item 6814.90.00 as articles of worked mica not specified elsewhere.
Mica Shim Stock Sheets
Mica shim stock sheets are precision-cut sheets of worked mica used as shims for aligning machinery in precision equipment. They are made from split mica, cut to exact thicknesses for spacing and leveling. These sheets fall under tariff item 6814.90.00 as other articles of worked mica for industrial use.
Mica Vacuum Tube Spacers
Mica vacuum tube spacers are stamped washers and spacers made from worked mica, used to insulate electrodes in vacuum tubes for radios and amplifiers. They are precision-cut to fit specific tube designs and provide thermal and electrical insulation. These spacers are classified under tariff item 6814.90.00 as articles of worked mica.
Mica Window Strips for Furnaces
Mica window strips for furnaces are transparent strips of split mica used as peephole windows in high-temperature furnaces and stoves. They are cut to size and polished, offering heat resistance without melting or cracking. These strips are classified under tariff item 6814.90.00 as worked mica articles.