The Eterna 1456U watch movement, which was in use from 1965 onwards, features a micro rotor and a double jewel bearing with 30 jewels. It incorporates a double excenter regulator for curb pins and stud carrier. The movement utilizes a self-winding gear that includes a pinion floating between two large jewels to facilitate direction switching. Additionally, the movement employs indirectly driven minute and second mechanisms, allowing for a relatively low profile. Since around 1966/67, minor modifications to the base plate and a simplified date driver have been implemented. The movement offers automatic winding, a sweep second hand, and a date function that can be set by changing the 23-24 hour interval. From approximately 1966/67, the date can be set by changing the 22-24 hour interval.