The Fontainemelon 636 is a mechanical watch movement that was manufactured from 1955 to 1962. It features an open face calibre with a winding gear that has a rocker on the back side. The movement includes a timer function with measurements of 0.1 seconds (0.01 seconds), 6 seconds, and 6 minutes, operated by a pillar wheel. Additionally, it has a stem winding mechanism and sub dials for 1/100 seconds, seconds, and minutes. The movement is equipped with a stop over wheel on the escape-wheel arbor for precise 1/100 second timing.