The Omega Speedmaster was introduced in 1957 as a racing chronograph. Through no action of Omega’s marketing department, the watch became a classic in its own time. Omega Speedmasters were discovered by professionals. They were used by pilots and astronauts, receiving the highest honor awarded to a watch; the astronauts would wear their Speedmasters to the moon in the Apollo missions.



Aleksey A. Leonov practices with a training mock-up of the ASTP commemorative medal during Apollo Soyuz Test Project (ASTP)
Omega movement (Lemania 1873 base movement)
With the The Flightmaster c.910 (ST145.013) the base c.861 Omega manual-wind movement is modified by replacement of the small seconds sub-register at 9 o'clock and with a 24-Hour AM/PM indication. Operation is the same as the c.911 above but with the omission of the small second indicator there is no way to determine at a brief glance if the watch is ticking unless the chronograph is in operation.
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