Section 16 Machinery and mechanical appliances; electrical equipment; parts thereof; sound recorders and reproducers, television image and sound recorders and reproducers,and parts and accessories of such articles 84 Nuclear reactors, boilers, machinery and mechanical appliances; parts thereof 84 83 Transmission shafts and cranks; bearing housings; gears...; flywheels... 84 83 90 Toothed wheels, chain sprockets and other transmission elements presented separately;.. Commodity Code Description 84 83 90 00 Toothed wheels, chain sprockets and other transmission elements presented separately;..