The Eterna 12670 watch movement features an integrated winding gear, eliminating the need for attachment to a manual-wind calibre. This design choice resulted in an acceptable height for the movement. Notably, the sweep second hand is smoothly operated through the use of a magnet in a bushing, replacing the traditional friction spring. Additionally, this movement incorporates automatic winding functionality and offers the convenience of a date feature, which is adjusted by changing the time from 22 to 24 hours. The Eterna 12670 movement was commonly used during the approximate period of 1958.