GLEN TITHER - MY NEW OMEGA SPEEDMASTER PROFESSIONAL WATCH 'MOONWATCH'

NASA supplied each of the Apollo astronauts with a standard issue Omega Speedmaster Professional manual-wind wristwatch (pictured above) together with Velcro strap. Unlike almost all other Apollo equipment, the watch was not manufactured for use specifically by NASA or in space but had been on sale in retail outlets in Houston and all of the United States from 1957-c1966 as the "Speedmaster" and as the "Speedmaster Professional" thereafter. Beginning in about 1962, NASA purchased examples of a number of commercially available watches for evaluation.
Aside from its primary and obvious function, the Omega Speedmaster Professional also incorporated a chronograph (stopwatch) via the large third hand on the watch dial. The three interior dials on the face provided respectively a) a second-hand, ancillary to the conventional time function b) a minute elapsed counter for the chronograph and c) an hour elapsed counter, again related to the chronograph function. The outside of the dial included a fixed bezel incremented to act as a Tachymeter (to measure miles per hour) in conjunction with the stopwatch function, hence the title "Speedmaster".
The timepiece was intended to be worn for intra and extra vehicular activties including the moonwalks on all the missions. Inside a pressurised environment the watch was worn conventionally but during EVA (extra vehicular activity) the astronauts wore the watch on the outside of their pressure suits, the long Velcro strap was designed to accommodate this change in 'wrist' dimension.
The Speedmaster had initially been worn on many of the pre-Apollo NASA manned space missions after satisfactorily passing exhaustive tests aimed at determining performance reliability in the conditions likely to be experienced during EVA. The first American to walk in space Edward H. White wore a Speedmaster during his Gemini 4 spacewalk and there are some unconfirmed reports that suggest the manufacturer only discovered its use by NASA after that event.
This model is still worn by many present day astronauts on Shuttle missions.