Speedmaster Moonwatch 39.7 321

In Context

At 39.7 mm it sits just under the modern norm — the band that suits the widest spread of wrists. The case back is open, so the movement is visible without taking the watch apart, and the sapphire crystal will resist everything short of deliberate abuse. 50 m covers rain and hand-washing comfortably; it is not a watch to swim in.

The movement is hand-wound, so winding it becomes part of the day rather than something the watch does for you. 55 hours of reserve is enough to set it down on Friday evening and find it still running on Monday. At 18,000 vph the seconds hand advances 5 times a second, the slower and more audible rate of an older design.

311.30.40.30.01.001 stands on its own in this catalogue — no other reference here shares its base number. It pairs a black matte dial with a stainless steel case. Introduced in 2020. Beyond the time it carries a chronograph.

The column-wheel chronograph Omega put back into production in 2019, fifty years after retiring the original. The 321 descends from the CH 27 architecture Omega developed with Lemania in the 1940s, and ran the Speedmaster from the CK2915 of 1957 until the 861 replaced it in 1968. The reissue is assembled in a dedicated atelier in Bienne, a couple of thousand a year at most.

3 other watches in the library run the Omega 321 B.

Omega

Speedmaster 321 38.6

311.50.39.30.01.001 · 38.6 mm

Omega

Speedmaster Professional Moonwatch 321 Platinum / Black / Alligator

311.93.42.30.99.001 · 42 mm

Omega

Speedmaster Professional Moonwatch 321 Platinum / Black / Bracelet

311.90.42.30.99.002 · 42 mm