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 21 Orthopaedic appliances; splints, etc; artificial parts of the body, etc 90 21 40 Hearing aids, excluding parts and accessories 90 21 40 00 Hearing aids, excluding parts and accessories Commodity Code Description 90 21 40 00 000 Hearing aids, excluding parts and accessories