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 18 Instruments and appliances used in medical, surgical, dental... 90 18 49 Dentists' chairs incorporating dental equipment Commodity Code Description 90 18 49 10 Dentists' chairs incorporating dental equipment 90 18 49 90 Other instruments and appliances, used in dental sciences