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 21 Centrifuges;incl centrifugal dryers,filtering/purifying machinery...for liquids or gases 84 21 31 Intake air filters for internal combustion engines Commodity Code Description 84 21 31 00 Intake air filters for internal combustion engines