Perpetual calendar with retrograde date hand. Day, month and leap year in apertures. Moon phases. Sweep seconds. Diameter: 28 mm. Thickness: 5.36 mm. Number of parts: 368. Power reserve: min. 35 hours - max. 45 hours. Winding rotor: 21K gold central rotor. Frequency: 28,800 semi-oscillations/hour (4 Hz).
