Section 18 Optical, photographic, cinematographic, measuring, checking, precision, medical or surgical instruments and apparatus; clocks and watches; musical instruments; parts and accessories thereof 91 Clocks and watches and parts thereof 91 12 Clock cases and cases for other goods of this chapter, and parts thereof 91 12 20 Cases 91 12 20 00 Cases Commodity Code Description 91 12 20 00 000 Cases
