The Wittnauer 11KAS watch movement was introduced between 1949 and 1950 as the first automatic-family movement with a ball-bearing rotor. It underwent variations due to the change from T- to U shock devices and a modified calibre, resulting in different versions. The extent to which all calibres were produced in the TC variant is unknown, thus only the known versions are documented. The UT signatures were also changed to UC. The movement features automatic winding, a sweep second hand, and a date function.