The Bettlach 8157 watch movement features an excenter regulator for the stud carrier, along with a patented double-excenter winding mechanism utilizing jewelled rollers. It incorporates a jewel-bearing rotor and includes an intermediate wheel between the minute pinion and the rest of the train, allowing for a large balance while maintaining a low profile and sturdy construction. The movement enables the placement of a center seconds wheel or a sub second, without requiring additional modifications. Additionally, this automatic movement offers sweep seconds and a date function, which can be adjusted by changing the time from 20:45 to 24h. The Bettlach 8157 is typically utilized from the period of 1960 onwards.