Monochrome Watches
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The Omega Seamaster Planet Ocean 600m GMT Master Chronometer

Giving credits to an overlooked, but really impressive model

| By Brice Goulard | 6 min read |
Omega Seamaster Planet Ocean 600m GMT Master Chronometer

While the Speedmaster remains Omega’s most successful watch, specifically since the renewal of the collection recently, the other important pillar in the collection if, of course, the Seamaster. Past years have seen the brand focusing mostly on the Diver 300M. Yet, there’s another dive watch that deserves some attention, an even more powerful model with proper diving credentials, the Planet Ocean 600m. Recently, we got our hands on a model that we consider to be sort of a hidden gem in the collection… This is the Omega Seamaster Planet Ocean 600m GMT Master Chronometer and we give a closer look at it. 

Neither the concept of an Omega Seamaster Planet Ocean 600m GMT nor this actual watch is new. In fact, the concept came on the market in 2013 and the watch we’ll be looking at today has been launched in 2016. Still, it is part of these watches that somehow didn’t get the recognition it truly deserves. This traveller’s PO 600M is a watch that has A LOT to offer, whether regarding its specifications, its actual overall execution or its look, with a monochromatic colour scheme that is something we somehow need to love here… (well, we actually love it, not just because we’re named MONOCHROME).

Omega Seamaster Planet Ocean 600m GMT Master Chronometer

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If today the PO 600M has been recently a bit neglected, due to the launch of the updated Diver 300M collection, it remains one of the most purposeful and comprehensive collections of high-end dive watches around, and that since its introduction in 2005. It is also a highly powerful watch, fully equipped for deep diving and built with impressive overall quality. Multiple variations have been created, including classic time-and-date models as well as chronographs, but the GMT only came in 2013, with this model. The combination of diving and traveller’s credentials is a classic for the industry and makes for some of the most practical models you can think of.

In 2016, the Omega introduced a whole new collection of Seamaster Planet Ocean 600m, including revised time-and-date models with new materials, colours and mechanics – namely, Master Chronometer movements – as well as this new edition of the GMT model. And while the brand has for long focussed on contrasting bright colours for the collection, this one plays on an opposite theme, being black and white… but striking nevertheless.

Omega Seamaster Planet Ocean 600m GMT Master Chronometer

The fundamentals of the collection are well present here and the Planet Ocean 600m GMT remains faithful to the basics; a 43.5mm case in stainless steel, typically Seamaster twisted “lyre” lugs, combination of brushed surfaces and polished bevels on the sides, robust case with screw-down crown, helium escape valve and external bezel and, as indicated by its name, a 600m water-resistance.

Omega Seamaster Planet Ocean 600m GMT Master Chronometer

The Planet Ocean 600m has always been a large watch, available in various sizes. Yet, even in its smaller editions, it is a watch with a strong wrist presence. This GMT edition, measuring over 43mm across and 17mm in height, is no exception to the rule. However… It is a watch that deserves more than just a look at the specification sheet. It needs to be tried on the wrist as its conception is clever, specifically when worn on the present strap. First of all, while the thickness can’t be forgotten, the case wears smaller than expected, with a 49mm lug-to-lug dimensions – which isn’t that large for such a watch – as the case is short. In addition to that, the way the bracelet is attached to the watch and wraps the wrist reinforce this sensation of compactness. All in all, the watch is certainly large but far more comfortable than expected – and mostly, very balanced and firmly in position. The strap, with its rubber lining covered with a black alligator insert, is closed by a folding clasp and its execution is really pleasant.

Regarding the rest of the habillage, the most obvious evolution between this Seamaster Planet Ocean 600m GMT and a classic time-and-date model is the bezel. No more unidirectional bezel with a 60-minute scale here but a bi-directional bezel with 24 very smooth clicks and a specific 24h insert. This is the main difference with another Planet Ocean 600m GMT, the “Deep Black”, which benefits from a larger diameter and use the extra space on the dial to relocate its 24h scale, thus keeping the 60-minute scale on the bezel. 2 watches with a slightly different vocation, the present version being slightly more “travel-focused”.


A note concerning this ceramic insert; it was in 2016 the first-ever bi-ceramic part made by the watch industry. While Rolex already had a two-tone insert (blue-black or blue-red), it was actually made in one colour first and treated afterwards to get the two colours. Omega managed to have two separated colours of ceramic here, without the need for a surface treatment… and what today appears as a standard for the industry, with ceramic being used by most brands, was still highly innovative only 5 years ago…

Omega Seamaster Planet Ocean 600m GMT Master Chronometer

The ceramic insert is made of black and white ceramics, with the white area classically representing daytime while the black part is devoted, you’ve guessed it, to night hours. The overall watch feels solid as a rock and the level of precision is, as you’d expect from Omega, very high.

Omega Seamaster Planet Ocean 600m GMT Master Chronometer

Moving to the dial, the black and white theme continues, as well as the use of ceramic. Indeed, the base plate for the dial is also made in polished black ceramic, which is discreetly engraved below the axle of the hands. Other than an additional 24h marking the presence of the GMT complication, this model shares most elements with its time-and-date counterparts, with arrow hands, faceted applied markers and Arabic numerals at 6, 9 and 12 o’clock. All the elements are generously filled with luminous material. And the black-and-white theme makes for a slightly more formal style than the orange or blue time-and-date versions, devoted to sports only.

Omega Seamaster Planet Ocean 600m GMT Master Chronometer

Under the sapphire crystal, the brand’s in-house Calibre 8906 is at centre stage. The base for this movement is well-known amongst Omega’s collection, being the 89xx – used in the Globemaster, the Aqua Terra 150m, the Constellation and more… This automatic movement, more powerful than the 8500 as featuring two barrels for a 60h power reserve, benefits from the entire lineup of technologies offered by Omega – co-axial escapement, METAS tests, anti-magnetic properties, silicon parts, free-sprung balance. As the 8906, it receives an additional GMT complication, which is adjusted exactly as it should, meaning that it is the local time that is adjusted by one-hour increments (and not the 24h hand, as in ETA or Sellita movements).

Omega Seamaster Planet Ocean 600m GMT Master Chronometer

Thoughts & Price

The Omega Seamaster Planet Ocean 600m GMT Master Chronometer (ref. is an impressively well-built watch, with an execution that pays tribute to the name on its dial. The look, with this entire b&w scheme, is also very attractive and brings the focus on the GMT complication, yet the diver’s credentials aren’t forgotten. Now, it certainly needs a man with a large wrist but that being said, it feels more comfortable than expected.

This version on rubber/leather strap is priced at EUR 7,500. It can also be ordered on a stainless steel bracelet, for EUR 7,800. More details to be found at

5 responses

  1. Black and white with an over tone of brown ? For a narrow group I guess ?

  2. Very interesting write up about an underrated watch. There is a lot to recommend the PO GMT not least that it wears a lot smaller than the dimensions suggest. I note as well that the construction of the bezel has been explained in the article as it is a point that many reviewers do not mention or get wrong. The thickness issue is really not a problem it is only 1mm thicker than the standard PO three hander. This is not too bad for a 600M water resistant watch with a display case back. I expect the comment that the Cal.89xx family of movements is “more powerful” than the older Cal.85xx family might raise some eyebrows but as the reviewer has stated the Cal.89xx movements are all METAS tested as a result their power reserve and chronometric performance at full wind and at 33% of the power reserve is fully tested and has to be stable and perform within the stated parameters. This testing regime was not applied to the Cal.85xx movements. My reading on the article suggests that this is exactly what the reviewer is alluding to. As for the claim that the monochrome colour way has nothing to do with Monochrome liking the watch let’s just say I think it has a little bit to do with it! The watch is stunning in real life. It would make a great basis for a Monochrome Watches collaboration with Omega, perhaps with a white dial with blackened hands and markers or a fully black bezel with white hours and minute markers. Just a thought.

  3. The previous PO GMT I thought looked superb but I’m sorry to say the black and white looks like cheap plastic. I think omega have sold themselves short, this is a great watch but that ruins it for me,

  4. The simplicity of the bezel lends itself to a multitude of occasions. This watch can easily be dressed up or down and the function is perfect. Like many other collectibles thr over looked and understated tend to be the most popular in the future. I look forward to getting my hands on an Omega “Oreo” in the near future.

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