The ETA 9158 watch movement, utilized between 1961 and 1962, serves as the maiden German electrical wrist-watch calibre. Not self-starting, a pulled crown locks the balance in a position, from which it reliably commences upon crown pushing. Notably, late samples are equipped with a regulator pointer. Laco/Durowe's acquisition by the U.S. Time Corporation in 1959 caused these movements to be briefly branded as Laco. This movement boasts features such as an electromechanically controlled balance motor, a back crown, jumping sweep second, and an electrical and mechanical hack capability. Additional functions encompass electronic operation and sweep seconds.