A big part of these faces is showing off the new edge-to-edge display with curved corners, and as a consequence the full screen versions are only available on the Series 4. But the design team was still really proud of them and had to find a way to get around that – "While we were at it," Dye mentions, "we also did them all as circles because we wanted this to be available on other watches as well." So if you're on an older model you don't quite get the same effect, but you do at least get a taste of the action.