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 10 Complete watch or clock movements, unassembled or partly assembled (movement sets); incomplete watch or clock movements, assembled; rough watch or clock movements. 91 10 12 Incomplete movements, assembled Commodity Code Description 91 10 12 00 Incomplete movements, assembled