Section 18 Optical, photographic, cinematographic, measuring, checking, precision, medical or surgical instruments and apparatus; clocks and watches; musical instruments; parts and accessories thereof 90 Optical, photographic, cinematographic, measuring, checking, precision, medical or surgical instruments and apparatus; parts and accessories thereof 90 13 Lasers, other than laser diodes; other optical appliances and instrume nts, not specified or included elsewhere in this Chapter. 90 13 90 Parts and accessories of lasers and optical devices, nes, of 90.13 Commodity Code Description 90 13 90 00 Parts and accessories of lasers and optical devices, nes, of 90.13