Quote Originally Posted by nunya View Post
Not quite, Rolex reference 16520 used a movement based on the Zenith El Primero 400, it was simplified and had its beat rate reduced to 28,800, from 1988 to 2000.

Had a Chronomaster triple date for a while, great movement, beautiful to look at, but I moved it on as it was a little too dressy for my taste at the time, as I get older I do keep an eye one for one occasionally, and it'd have to be a recent service, full B&Ps and on a bracelet
Thanks for the clarity on the exact version used. I knew Rolex slowed the movement down for longer service intervals / better longevity of the movement.