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 26 Instruments/apparatus for measuring the flow... of liquid or gases, nes 90 26 90 Parts and accessories 90 26 90 00 Parts and accessories Commodity Code Description 90 26 90 00 000 Parts and accessories