The Certina 25-66 watch movement is similar to the ETA 717 movement, but with a lower position and an early Incabloc shock device. The exact differences between the Zentra 185 and Certina 25-66 are uncertain. Most samples of the Certina 25-66 movement feature two bridge layouts, as shown in the archive. However, there are also samples with different bridge layouts. The Certina 25-66 movement functions include manual winding, sub-seconds, and Incabloc Shock Protection. It was used during the period of approximately 1935.