Speedmaster Professional Moonphase Broad Arrow Stainless Steel / Silver / Strap

In Context

At 42 mm it is sized to the current mainstream: 40 mm is the median across every watch measured in this catalogue. 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. 45 hours of reserve carries it overnight, but not through a weekend in a drawer. At 21,600 vph the seconds hand advances 6 times a second, the slower and more audible rate of an older design.

3875.30.31 stands on its own in this catalogue — no other reference here shares its base number. It pairs a silver dial with a white gold, stainless steel case. Beyond the time it carries a chronograph and a moon phase.

Handwound chronograph movement with moonphase and date at 12 o'clock as found in the Omega Speedmaster Professional.

7 other watches in the library run the Omega 1866.

Omega

Speedmaster Professional Moonphase / Strap

3876.50.31 · 42 mm

Omega

Speedmaster Professional Moonphase / Bracelet

3576.50.00 · 42 mm

Omega

Speedmaster Professional Moonphase Broad Arrow Stainless Steel / Ivory

3875.20.37 · 42 mm

Omega

Speedmaster Professional Moonphase Aventurine / Strap

311.33.44.32.01.001 · 44.25 mm