2 Day ACHS-1 MIG Aircraft Clock АЧС-1 - USSR,1987s. The clock was produced at the Molnija Military Watch Factory,Chelyabinsk. All functions work. In addition to telling the time - main clock, the small dial on top shows the flight time. The lower dial is the stopwatch which functions by pressing the right button to start/stop/reset. Turning the right button starts and stops the seconds hand of the main clock. The left button winds and, pulled out to set the main clock. Pushing the left knob moves the colours in the little square window in the upper dial to start (red), stop (red/white), and reset (white). This clock is purely mechanical. The clock uses 27V only for an internal heating element to prevent condensation at low temperatures. The electric contacts are for the internal heater only. This type was used in the soviet military air force for the MiG-23, MiG-25, MiG-29 aircraft, strategic bombers, helicopters and transport aircrafts