There are two large cutouts
rolex ruby dial in the movement on the left – up top is the one for the function selector and below is the one for winding and setting. With the selector set to W, the lower "crown" winds, and with the selector at H you can
montre u-boat set the hands. The clutch for switching back and forth between the two is pretty interesting – it's the sliding arm
link right above the lower tip of the tweezers. Here's another still from the video.