Seamaster Planet Ocean 600M Co-Axial 45.5 Master Chronometer GMT Dark Grey

In Context

At 45.5 mm it is a large watch — well above this catalogue’s 40 mm median, and enough to dominate a narrow wrist. 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. 600 m is a professional diving rating, far past any demand a wrist is likely to make of it.

The movement winds itself from the motion of your wrist. 60 hours of reserve is enough to set it down on Friday evening and find it still running on Monday. At 25,200 vph the seconds hand advances 7 times a second.

215.92.46.22.99.002 stands on its own in this catalogue — no other reference here shares its base number. It pairs a grey matte dial with a titanium case. Introduced in 2023. Beyond the time it carries a gmt.

Self-winding movement with Co-Axial escapement. Certified Master Chronometer, approved by METAS, resistant to magnetic fields reaching 15,000 gauss. GMT and time zone functions. Free sprung-balance with silicon balance spring, two barrels mounted in series, automatic winding in both directions. Black ceramised grade 5 Titanium main plate and bridges. Special decoration made by laser ablation.