Felsa 4007

Date complication variant of the Felsa 4000 automatic movement. Features calendar function with date set by advancing time through 21:00-24:00 hours. Introduced around 1955 alongside the base 4000 caliber. Shares the innovative rocking bar changer for bidirectional winding and modular construction based on the manual-wind 4010 platform. Part of the successful 4000 series used in many mid-century Swiss watches.