GregH
路what does that 7 circles do? ...
I'm guessing power reserve.
Interesting article on the person this watch commemorates, free diver Jaques Mayol.
https://erwangrey.wordpress.com/2015/02/11/the-omega-seamaster-apnea/
"the seven circular apertures on the dial represent the special apnea timing function, for those who venture underwater without any breathing apparatus. When the start-stop pusher at 2 o鈥檆lock is pressed, the seven apertures on the dial successively fill with red each minute from left to right. Once the first seven-minute cycle is complete (and all the apertures are red), the colour successively reverts to the background colour of the dial (black or silver), allowing in total a 14-minute cycle to be timed."