The Omega Speedmaster Mark III is an important piece, in that it is the first automatic Speedmaster. It was also aggressively bold in design. Omega referred to the as part of the “pilot” design family, like the flightmaster that came before it, but the Mark III’s design is like a flightmaster cranked up to 11, with steeper angles that make it resemble a traffic cone or volcano. Omega referred to the shape as “anatomic” in that it was designed for comfort to conform to the shape of the human wrist. It also looks like there’s an inch between the crystal and the dial. Omega promoted the Mark III heavily alongside the traditional Moonwatch and the Mark II, which itself looked big and bold until the Mark III came along. Omega advertised it from 1972 through 1975, and it came in multiple dial colors. Interestingly, Omega labelled some later versions of the Mark III as “professional”, though I’ve never seen anything to indicate why it was initially not considered “professional” but later switched.