The France Ebauches 163 is an open face calibre watch movement that features varying bridge shapes. It is likely to include a left-handed ratchet-wheel screw. Not much is known about the differences between the Unitas 283, 291, 297, 309, 329, 333, 337, and 499 movements. The France Ebauches 163 movement offers the functions of stem winding and setting, as well as a sub-second display. It was primarily used around the year 1940.