Most of you guys are younger than my Omega!
My Omega is a Speedmaster ST 145.012 made on October 22, 1968- this was the very last week of production of the .321 movement. Afterwards, the cheaper .861 movement was used.
All Speedmasters from 1957 thru the present are commonly called the "Moonwatch", but the ST 145.012 is the model most likely to have been worn on the first Apollo moon landing in July of 1969. No one will ever know for sure because Neil Armstrong left his on the LEM and Buzz Aldrin's was stolen in 1971 when he shipped his personal items to the Smithsonian.
My good friend Claude Monser, a WWII pilot, owned this watch since 1968. I didn't pay much attention to it, but he was quite proud of it. He died in 1999, and his widow asked me to sell his watch on EBay. But while researching its value, I realized its historical significance, and bought it for myself.
It's fairly easy to unscrew the back and carefully move the regulator lever to adjust how fast or slow it runs. I've had it down to + or - a few seconds a day and, as mentioned previously, it will run at different speeds depending upon what position you leave it in overnight.
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