The THOMMEN CM20 is a Swiss Made precision, multi-functional chronometer designed to operate under the most stringent operating conditions in civil and military aircraft. The CM20 is designed according the latest civil and military avionics standards.
It features a three line display with light digits on dark background (negative image). It supports the simultaneous indication of a combination of clock- and timer-function reading and has several day/night mode backlight options including NVIS A and B compatibility.
The time base is supplied by a dedicated internal power reserve to provide the timekeeping function even when the aircraft power is removed.