The Longines 993.2 watch movement, used from 1957 to 1962, is a chronometer equipped with a sweep second function. Early samples of this movement consist of 28 jewels. Notably, the winding gear is integrated into the movement, rather than being attached to a manual-wind calibre, resulting in an acceptable height for that time. Enhancing its uniqueness, the indirect sweep second is smoothly controlled by a magnet in a bushing rather than a friction spring, where the end of the sweep-second arbor runs on a polished surface. Further functions of the movement include automatic winding, as well as a hack feature.