Section XVI · Nuclear reactors, boilers, machinery and mechanical appliances; parts

8483.40

Gears and gearing, other than toothed wheels, chain sprockets and other transmission elements entered separately; ball or roller screws; gear boxes and other speed changers, including torque converters:

How this code is built
84

Chapter

Nuclear reactors, boilers, machinery and mechanical appliances; parts

83

Heading

The product family within the chapter

40

Subheading

The specific good, identical worldwide

The first six digits are the same in every country that uses the Harmonized System. The United States adds two more for the tariff rate and, often, two more for statistics — which is why the rates below are listed against 8- and 10-digit numbers rather than against this code.

How the schedule reaches this code

  1. 84Nuclear reactors, boilers, machinery and mechanical appliances; parts
  2. 8483Transmission shafts (including camshafts and crankshafts) and cranks; bearing housings, housed bearings and plain shaft bearings; gears and gearing; ball or roller screws; gear boxes and other speed changers, including torque converters; flywheels and pulleys, including pulley blocks; clutches and shaft couplings (including universal joints); parts thereof:
  3. Gears and gearing, other than toothed wheels, chain sprockets and other transmission elements entered separately; ball or roller screws; gear boxes and other speed changers, including torque converters:

Published US duty rates

Duty is set at the 8- or 10-digit line, not at this 6-digit subheading, so more than one rate can sit under this code.

  • 8483.40.10.00Torque convertersNo.
    General
    Free
    Special (FTA)
    —

    No preferential rate published.

    Column 2
    27.5%

    Countries without normal trade relations.

  • 8483.40.30Imported for use with machines for making cellulosic pulp, paper or paperboard
    General
    Free
    Special (FTA)
    —

    No preferential rate published.

    Column 2
    27.5%

    Countries without normal trade relations.

  • 8483.40.50Other
    General
    2.5%
    Special (FTA)
    Free (A*,AU,BH,C,CL,CO,D,E,IL,JO,KR,MA,OM,P,PA,PE,S,SG)

    Only if the goods qualify under one of these programs.

    Column 2
    27.5%

    Countries without normal trade relations.

  • 8483.40.70.00Other speed changersNo.
    General
    25¢ each + 3.9%
    Special (FTA)
    Free (A*,AU,BH,C,CL,CO,D,E,IL,JO,KR,MA,OM,P,PA,PE,S,SG)

    Only if the goods qualify under one of these programs.

    Column 2
    $4.50 each + 65%

    Countries without normal trade relations.

  • 8483.40.80.00Ball or roller screwsNo.
    General
    3.8%
    Special (FTA)
    Free (A*,AU,B,BH,C,CL,CO,D,E,IL,JO,KR,MA,OM,P,PA,PE,S,SG)

    Only if the goods qualify under one of these programs.

    Column 2
    45%

    Countries without normal trade relations.

  • 8483.40.90.00Gears and gearing, other than toothed wheels, chain sprockets and other transmission elements entered separatelyNo.
    General
    2.5%
    Special (FTA)
    Free (A*,AU,B,BH,C,CL,CO,D,E,IL,JO,KR,MA,OM,P,PA,PE,S,SG)

    Only if the goods qualify under one of these programs.

    Column 2
    27.5%

    Countries without normal trade relations.

Schedule footnotes

  • See 9903.88.01.
  • See 9903.90.08.
  • See 9903.88.03.

A reference to Chapter 99 means an additional action — a Section 232 or 301 measure, an exclusion, or a quota — applies on top of the rate above.

This is the listed rate. Antidumping and countervailing duty orders, Chapter 99 actions and preference qualification all change what is actually collected, and classification is a judgement about your goods. Verify with your licensed customs broker before you file.

Other subheadings in heading 8483

Source: U.S. International Trade Commission (USITC) — 2026 HTS Revision 12, released 2026-07-21, published at hts.usitc.gov. A U.S. Government work in the public domain.