The Certina 13-50 watch movement is an open face calibre available with options such as a bimetallic screw balance and a Breguet hairspring. It comes in different sizes with heights ranging from 4.2mm to 5.9mm including 18.5 and 19''' variations. There are multiple bridge layouts, two base plates with varying dial-feet positions, and slightly differing setting-lever springs. The movements are grouped under FHF 1 to 14, with calibres such as FHF 1144, 2144, 2146, 4144, and 4146 belonging to these groups. The movement designation starts with FHF 22 for individual calibres. The Certina 13-50 movement offers functions like stem wind and set, as well as a sub second hand. It is estimated to have been used around 1940.