Section 16 MACHINERY AND MECHANICAL APPLIANCES; ELECTRICAL EQUIPMENT; PARTS THERE OF; SOUND RECORDERS AND REPRODUCERS, TELEVISION IMAGE AND SOUND RECORD ERS AND REPRODUCERS, AND PARTS AND ACCESSORIES OF SUCH ARTICLES 84 Nuclear reactors, boilers, machinery and mechanical appliances; parts thereof 84 21 Centrifuges, including centrifugal dryers; filtering or purifying machinery and Commodity Code Description 84 21 11 84 21 12 84 21 19 84 21 21 84 21 22 84 21 23 84 21 29 84 21 31 84 21 32 Catalytic converters or particulate filters, whether or not combined, for purifying or filtering exhaust gases from internal combustion engines 84 21 39 84 21 91 84 21 99