Cortébert 677

The Cortebert 677 is a manual-winding movement introduced in 1886. It measures 12 lignes in diameter and features 15 jewels with no shock protection. The open-face calibre model 5 includes a bimetallic screw balance, Breguet hairspring, and sub-second display, notable for its negative stem mechanism with rocker bar and ratchet positioned under the base plate. Production continued until approximately 1894.