Section 18 Optical, photographic, cinematographic, measuring, checking, precision, medical or surgical instruments and apparatus; clocks and watches; musical instruments; parts and accessories thereof 91 Clocks and watches and parts thereof 91 14 Other clock or watch parts 91 14 10 Springs, including hair-springs 91 14 10 00 Springs, including hair-springs Commodity Code Description 91 14 10 00 000 Springs, including hair-springs
