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 02 Lenses, prisms, mirrors and other optical elements, mounted, nes 90 02 90 Other optical elements Commodity Code Description 90 02 90 00 Other optical elements