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 90 18 49 ** Dentists' chairs incorporating dental equipment Commodity Code Description 90 18 49 10 000 Dentists' chairs incorporating dental equipment 90 18 49 90 000 Other instruments and appliances, used in dental sciences