The Bettlach 8460-73 watch movement, known as the early Chonometro Gondolo, is an open face calibre featuring a bimetallic screw balance and a Breguet hairspring. It utilizes a moustache lever for enhanced accuracy and has a pink-gold train. The movement incorporates a wolf teeth winding gear and a flying barrel with Geneva stopwork. The Bettlach 8460-73 movement is equipped with stem wind and set functionality, as well as a sub second function. This particular movement was used around the year 1872.