Some tachymeter/telemeter/pulsometer watches featured spiral-fashion “snailed” scales around the dial. For that Chronoscope, Omega opted for a more symmetrical look that includes a several concentric circles that include the vital scale details while also not materially distracting from core dial legibility. The advent of the first Submariner Day, the 1680, https://www.watchesworld.com/frozen-in-time-luxury-watches-for-winter/