Omega Seamaster Planet Ocean 600M 42 mm 217.30.42.21.01.001

Imagen: Omega, web oficial

The storyWhy this reference matters

The Planet Ocean arrived in 2005 because Omega wanted something more serious than the everyday Diver 300M: six hundred metres, a broad bezel, twisted lyre lugs and, at ten o'clock, the helium escape valve. It worked, and over the years it grew. The second generation in 2011 brought a ceramic bezel; the third, in 2016, Master Chronometer certification. By then the standard 43.5 mm case had put on weight to 16.1 mm, and the watch had real presence in every sense of the phrase.

In 2025 Omega stripped it right back. Diameter down to 42 mm, height to 13.79 — better than two millimetres off. The lyre lugs, the twisted ones Omega has been putting on its divers for decades, are gone, replaced by faceted, angular ones with broad polished chamfers. The dial loses its date window. And the helium valve, the most photographed detail in the family, goes straight in the bin.

The valve existed for saturation divers, who spend days in helium chambers: the gas works its way into the case and has to get back out during decompression. Omega's answer this time is structural, borrowed from the six-thousand-metre Ultra Deep, which doesn't have a valve either. A titanium ring around the crystal stiffens the whole assembly and seals it. Fewer holes in the case, fewer things to go wrong, and one less story to tell at the bar.

SpecificationsThe numbers, in one table

IdentificationHow to tell it apart

The quickest check is at ten o'clock: if a helium valve pokes out of the case, this isn't the generation you're looking at. Then the lugs, faceted with a wide polished chamfer rather than the lyre twist of every Planet Ocean before it. And the dial, with no date window at three, because the calibre 8912 doesn't offer one.

Reference 217.30.42.21.01.001 is the steel case on a steel bracelet; the 217.32 references are the rubber-strap versions. The 01 in the second-to-last block marks the black bezel — blue is ...002, orange ...003. The insert is polished ceramic with the sixty-minute scale in white enamel, and the case back isn't sapphire but screwed grade 5 titanium, with the seahorse engraved on it.

You can spot the bracelet from across a room: three rows of flat links, the outer ones brushed and the centre row polished, on a folding clasp with a six-position micro-adjustment and a dive extension. Lug width 21 mm, 47.5 mm lug to lug on a 42 mm case.

CollectingWhat collectors check

This reference has only just landed, so nearly everything on the second-hand market will be as new and the decision isn't about condition — it's about specification. Bezel colour, and above all bracelet or rubber. The rubber versions carry their own reference, 217.32, and buying the steel bracelet separately afterwards is expensive enough that paying the difference up front usually works out.

What does deserve a loupe is the enamel scale on the bezel. A chip in the enamel isn't repaired — the whole insert gets swapped. Check the edge of the ceramic too, and work the clasp's micro-adjustment back and forth a few times, since it's the part that gets handled every day and the first to play up. Ask for the METAS card.

If you're coming from the previous generation, try one on before you commit. Take 2.3 mm off the height and a millimetre and a half off the diameter and it wears like a different watch — anyone who liked the old one's heft may not get on with this at all. And mind the date: there isn't one. If you use a date daily, your Omega is the Aqua Terra or the Diver 300M.

Common questionsWhat people ask us about this reference

Keep readingWhere to go from here

Close relativesThe ones it gets confused with