The Speedmaster Mark II was the first departure from the classic Speedmaster (Professional) design, which at the time of introduction (1969) had more or less reached its final stage. It is said to be intented to replace the classic Professional, although this never actually happened.
The Speedmaster Professional Mark II ST 145.014 as pictured here has a stainless steel case and matching bracelet. The dial is grey with orange accents - the so-called 'Racing' version. is fitted with the more common Tachymeter glass.