https://www.youtube.com/watch?v=IwXdxUYn3kg
This stopwatch intended for measuring time in minutes, seconds and fractions of a second may be handy when conducting sports competitions as well as in scientific research work and motion-time study.
Clockwork: caliber 42 mm, 16 jewels, spring actuator, lever escapement, balance-spiral oscillator system with 0,4 s oscillation period.
Single complete winding operation time: 18 h, minimum.
Hands: controlled by a special summing-effect device provided in stop-watch clockwork. Started and stopped by depressions of winding crown and reset to zero by depression to button.
60-second stop-watch dial, with 0,2-second division value. 60-min counter, with 1-min division value. Chrome-plated metal case.