The Unitas 159 is an open face calibre watch movement with a setting lever positioned between the plates. This lever protrudes from the movement during the setting process, and the movement is typically only accessible when the crown is in the winding position. It features a bimetallic screw balance with two adjustment screws. Additionally, the movement offers options such as a Breguet hairspring and Reed's regulator. The Unitas 159 belongs to a series of movements that underwent experimentation, as evidenced by the existence of variants I and II with different setting bridges. This movement was commonly used around the year 1910 and provides stem winding and setting functionality, as well as a sub-second function.