The Omega 341 watch movement, introduced during the period of 1949-1950, was the first automatic-family watch with a ball-bearing rotor. It underwent modifications including changing from the T- to U-shock device and a modified calibre, resulting in various variants. However, it is uncertain if all calibres were produced in the TC variant. Also, the signatures of UT versions were altered to UC. This movement features a detached manual wind and includes functions such as automatic winding and a sweep second hand.