Breguet caliber 558QP3
Retrograde dates indication at 12 o'clock, days at 9 o'clock, and months and leap years at 3 o'clock. Small seconds on the tourbillon axis. Manually wound movement with tourbillon and perpetual calendar. Numbered and signed BREGUET. Cal. 558QP3. 14 ½ lines, 21 jewels. Power reserve of 50 hours. Lateral lever escapement and balance with adjustment screws on a Breguet spring. Frequency 2,5Hz. Adjusted in six positions.