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 11 Compound optical microscopes, including those for photomicrography, cinephotomicrography or microprojection. 90 11 20 Other microscopes, for photomicrography, cinephotomicrography or microprojection Commodity Code Description 90 11 20 00 Other microscopes, for photomicrography, cinephotomicrography or microprojection