This is one of my favorite auto chronograph watch I used to own. It exudes masculinity with large diameter, thick dimension, and hooded lugs. It wears big and thick, yet comfortable.
Even though the watch condition is not mint or pristine, I fell in love with this vintage watch. It was okay, good enough for me. Immediately after this acquisition, I was looking for a good example of Mark II and Mark III, but luck has run out on me. In the end, I regretfully sold this watch to fund other purchase.
Watch diameter 42mm (excluded crown).
Weight 145gr with bracelet
24hr counter @ subdial.
Central minute and second counter.
Based on Lemania 1340 (starting production year approx 1972), caliber 1040 was one of the most complicated and robust automatic chronograph movement at that time.
Omega cal 1040 (modified Lemania 1340).
Movement dimension: diameter 31mm, thickness 8mm.
28.800bph, 45hr power reserve, 17 jewels.
Cam lever design.
For further information regarding Speedmaster Mark series, please look at an article written by the late Chuck Maddox here.
Some more pics: