The Cortebert 671 is an open face calibre with a bimetallic screw balance and a Breguet hairspring. It features a lever with hidden pallets and a counterweight, as well as a barrel with Geneva stopwork. The precise origins of the ebauche used in this movement are uncertain, as the Landeron signature is overwritten, possibly indicating involvement from both Alpina and Landeron. The functions of this movement include stem wind and pin set, along with a sub second display. The Cortebert 671 movement was typically used around the period of 1895.