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 07 Spark-ignition reciprocating or rotary internal combustion piston engines. 84 07 21 Other 84 07 21 90 Other Commodity Code Description 84 07 21 90 00 Other