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 19 Mechano-therapy appliances; massage apparatus... respiration apparatus 90 19 20 Ozone, oxygen and aerosol therapy, artificial respiration or other therapeutic resp appa Commodity Code Description 90 19 20 00 Ozone, oxygen and aerosol therapy, artificial respiration or other therapeutic resp appa