It is this one: https://www.hodinkee.com/blog/found...o-the-peak-of-mount-everest-live-pics-details But I can't find the reference number and there seems to be a few Oyster Perpetual chronometer models around that time. Was it a Super Oyster or a standard screw down? I would not mind hunting one down. Some of you might have seen this article https://www.outdoorjournal.com/feat...verest-in-1953-putting-a-controversy-to-rest/ While being chiefly concerned with Rolex vs Smiths (spoiler alert: Smiths were the first to the summit), an Omega also makes an appearance: "Griffith Pugh, the scientist behind their success, wore his own Omega CK2287 chronometer." As he was the team's physician I wonder if he had a pulsometer scale? Some more Omega-specific info here: https://www.intlwatchleague.com/showthread.php?28685-An-Omega-on-Everest-in-1953!