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 01 Wrist-watches, pocket-watches and other watches, including stop-watches, with case of precious metal or of metal clad with precious metal. Commodity Code Description 91 01 11 With mechanical display only 91 01 19 Other 91 01 21 With automatic winding 91 01 29 Other 91 01 91 Electrically operated 91 01 99 Other