The face of the watch is about 6 feet across and with the band it's about 15 to 18 feet.
The Omega Speedmaster is the first watch worn on the moon.
~ from the Omega website ~
1969 - Apollo 11
After completing their giant leap for mankind astronauts used the Speedmaster to time proceedings during their 2.5 hour space walk on the lunar surface. The watch remains the first and only watch to land on the moon.