The ETA caliber C07.621 is a Swiss made automatic watch movement with a day-date function. It has 25 jewels and a beat rate of 21,600 vph, 3Hz. This caliber is essentially an evolution of the ETA 2836-2 and as a Powermatic 80 movement, it offers a more modern 80 hours power reserve. The C07.621 is available as a COSC chronometer certified movement. Despite some incorrect information online, this caliber is not equipped with a silicon hairspring or synthetic escapement.
This caliber is only available for use in Swatch Group brand watches such as Mido (cal. 80), Certina, and Hamilton (cal. H-30).
Note: This caliber listing is still being updated, but feel free to start discussions on it in the comments below…