Bidynator
From Chronopedia
Bydantor
Bidynator was a brand name for a series of automatic watch movements produced by Felsa from 1942 through the 1960's. It was the first successful movement with bi-directional winding.
Felsa introduced their first automatic movement with bi-directional winding in 1942. Cal. 410, and the associated ladies model, Cal. 380, were revolutionary but World War II interrupted production and development. Cal. 410 was only produced for a short while before the more-refined Cal. 690 was introduced in 1947 to replace it. These movements were very similar, with many interchangeable parts, but the new series had a longer power reserve (43 rather than 32 hours) and were produced in much greater volume.
