Chronometer Seamasters

Seamaster chronometers are an odd bunch. Chronometer certification was mostly reserved for the Constellation line-up, and by default, any Chronometer Seamaster is going to be more rare than a Constellation. In addition, they are also less expensive than Constellations making them attractive for entry-level collector. Chronometer Seamasters come in three movement categories distinguished by their movements: 564, 752, 551 and 352.

167.070551Rare, Factory redial
2577352Rare, Bumper
Chronometer Seamaster References and Movements

Of these, the cal 551 can be considered an edge case, because it is actually an Omega Geneve that has had dial changed by the factory. It has been listed here, because some completionist collectors may want to add it to their collection. This blog post focuses less on the day/date versions, because my personal interest resides in the date versions.

Omega Seamaster 168.024

This is probably the most popular of the chronometer seamasters due to the classic oyster-style case familiar from 14700 and 14744. They are characterised by a massive case with beefy lugs and they came with a beads of rice bracelet, a must have for an Omega dress watch enthusiast. It is possible to find these watches with and without cyclops on authentic Omega crystal. Apparently, cyclops was an option you could choose when buying the watch at the time.

The caliber 565 non-chronometer reference 166.010 shares the same case. In the end, there isn’t that much difference. While there is not certainty whether the chronometer version ever shipped with black dial, it is possible that there have been crosshair dial versions both with crosshair piercing the text and crosshair not piercing the text. I haven’t personally handled these watches or seen authoritative take on their existence. I treat all black dial Seamasters without visible radium / tritium plots as redials.

Omega Seamaster ‘Sparkle’ 168.022

The 168.022 comes in a large 36,5mm case and has a nice radial finish. It comes in a few dial variations, with most notable being the ‘Sparkle’ dial. 168.022 features a cal 564 movement and wears well.

The 168.022 have few different variants. Among these, there are a champagne dial and a white dial sparkle. The watches can have T SWISS T dials to indicate presence of tritium plots, but they can also be without tritium plots. Redials are easy to spot, because the dials are hard to reproduce. One should watch out for overly polished cases and cases where the radial finish of the bezel is gone. I haven’t personally seen a legit black dial version yet. They may exist, but July/2021 I assume they don’t.

Omega Seamaster 168.035

These watches are for the quirky 70s cushion case lovers. They are slightly bigger and wear a lot differently from the 36,5mm case Seamasters. The watches measure at 38mm diameter, but they wear a lot smaller due to the short lugs. In addition, the lug width is 22mm and the bracelets are nearly impossible (read expensive) to find loose. It is possible that there have been black dial version of these, but as of now (9/11/2021) this is unclear.

Suspicious black dial variant of the non-chronometer version 166.065. I was initially fooled by the tritium plots, but it may be that the dial is not original.


The 168.022 and 168.024 share the same case with Seamaster 60 ‘Big Crown’ ref 166.062 and various De Ville Chronographs (145.018, 145.017 and 146.017 among others). In addition the bracelets go to the Seamaster 120 case 135.027 / 136.027. Unsurprisingly, because the 1069/524 goes many, much more valuable watches, it is highly sought after by collectors and thus getting scarce and valuable. Interesting history behind 1069/524 is that there are also unbranded ones manufactured by JB Champion which can be used to provide extension links.

It is common to find collectors with 100s of bracelets that they have detached from watch heads and hoarded overtime. One can only speculate the reasons, but one of them is that selling a bracelet and watchhead separately will typically yield more money. As the result, it is not that common to find a chronometer Seamaster on its original bracelet as somebody has collected it into their dragons hoarde of vintage omega parts or mounted it on a more expensive watch.

Bracelet/EndlinksReferencesLug Width
1069/524168.022, 168.02319mm
1098/540168.022, 168.02319mm
1125/560168.022, 168.02319mm
1170/604168.035, 168.03422mm
Chronometer Seamaster Bracelets

Omega cal. 564 Movement

Cal 564 movement is beautifully crafted. The movement should be easy to wind and setting time should be smooth. Only thing to watch out for is a broken quickset date. The parts are not available outside of Omega and they are quite expensive. If one finds a watch with broken quickset date I’d consider not repairing it. In my eyes, broken quickset date doesn’t lower the value of the watch considering how easily they break.

The cal 564 movements are true workhorses. If the movement is not broken, they will wind and run despite years of neglect. For wear, service is recommended.

Türler Dials

Aside from the 2577, all of the watches can be relatively commonly found with Türler print. This is also a common thing that dodgy entry-level Rolex investors add later on, sometimes with a Sharpie and often completely ruining the dial.

Meister Dials

Based on my experience, Meister dials are applied in similar fashion as Türler, but less common (in my experience) than Türler dials. All the same, they can be found. Another favorite thing to add when preparing to make maximum profit.


The chronometer Seamasters are a nice category of vintage Omega watches from collector’s perspective. There are enough references and variants to offer plenty of challenge. Their overall collectibility is still quite low, which makes their prices still quite affordable aside from the elusive bumper chronometer. They are also common enough that there is a market and not all of them are yet in watch collectors dragons hoardes. In addition they are great watches to wear with eloquent dressy designs that stand time.

Omega Aqua Terra Railmaster 2504.52

Movement2402 (ETA 2892-A2)
Lug to lug44mm
Lug width19mm
MaterialStainless Steel
Water Resistance150m
Basic information

Omega Aqua Terra Railmaster is one of the first Omega Railmaster reissues from the early 00s. The watch features no-date 2403 movement and 3-6-9 dial present in the earlier references. The thing to note is that the Aqua Terra Railmaster is not an antimagnetic watch in the spirit of Eberhard Scientigraph, Rolex Milgaus, IWC Ingeniur or the original Omega Railmaster. Instead, as part of the Aqua Terra lineup, the 2504.52 Railmaster was perhaps meant to compete with Rolex Explorer.

The Aqua Terra Railmasters are defined by no date 3-6-9 dial, painted super luminova plots, screwdown crown and co-axial movement. The watches offer 150m water resistance making them durable companions to office dwellers, commuters and downtown mall spelunkers .


The 36mm Aqua Terra Railmaster was released during time when Omega lineup was based on the more is more principle. Similarly to the Planet Oceans, the Aqua Terra Railmaster was released in multiple configurations from 36mm to 49mm. Of these, the 39mm variant is the most popular and easily found. There has been discussion that the 41mm would be the rarest, but they seem to be available at any given moment unlike the 2504.52 or 2804.52 which show up few times a year.

ReferenceSizeLug widthDetails
2504.5236mm19mm1575/899 bracelet
2804.5236mm19mmLeather strap
2503.5239mm20mm1574/898 bracelet
2803.5239mm20mmLeather strap
2103.5239mm20mmYellow gold, yellow gold bracelet
2603.52.3739mm20mmYellow gold, brown leather strap
2603.52.3139mm20mmYellow gold, black leather strap
2502.5241mm21mm1573/887 bracelet
2802.5241mm21mmLeather strap
2806.52.3749mm24mmLeather strap, Manual wound gold, leather strap, manual wound gold, leather strap, manual wound
Aqua Terra Railmaster Chronometer references

If you’re “A Big Watch Guy” the 49mm Railmaster could be a good alternative IWC Pilot a good alternative. In a way, the most interesting reference is the 18k 2103.52 with the 18k gold bracelet. I don’t fancy owning one, but it’d be amazing to see one in person one day.


The bracelet features integrated clasp without any micro adjustments. The bracelet is a typical pin & collar bracelet of the era. The bracelet is robust and serviceable as pins take most of the wear and they can be replaced during the service. The downside is that for amateurs the bracelets can be difficult to adjust and it is easy to bend pins and lose collars.

Bracelet / EndlinkLug WidthBuckle
1575/899 19mm16mm
1574/898 20mm17mm
1573/887 21mm18mm (?)
Aqua Terra Railmaster Chronometer bracelets

For those who suffer from swelling, the bracelet may not be optimal as there is no micro-adjustment. Another issue is getting it properly fit as the size is controlled with half-links. As for the 2504.52, the 19mm to 16mm taper is proportioned and relatively standard and the bracelet is very comfortable.

For perfectionists and people who suffer from OCD, the bracelet design makes it nearly impossible to center the hidden clasp. This may be a serious downside depending on the mental condition of the watch enthusiast.


Field watches and nato straps go together like salt and pepper. The 2504.52 is no exception. For people who can’t live with a cheeky springbar, the 19mm lug width may be difficult to digest. However, if you take the peeking spring bar as a stylistic element, the Railmaster Chronometer can be worn with just about any 18mm Nato.

Another option is leather. I have yet to purchase a 16mm Omega Deployant clasp, but I’m planning to do so and get a quality leather, sailcloth and canvas for change.

Dial and Hands

The 3-6-9 dial is a throwback to the original Railmaster from 1950s. Aside from green super luminova, the Railmaster Chronometer has more text on the dial. The defining feature of the no-date dial is symmetry and simplicity. The dial of the 2504.52 is about the same size as 2201.50. This makes it a very good companion to the 42mm Planet Ocean of the same time. The 2503.52 has a slightly larger dial than 2201.50, which may look out of place next to such imposing dive watch.

With the hands, there comes a major difference to the original railmaster. The original Railmaster has Ranchero style hands with Arrow hour-hand whereas the Aqua Terra Railmaster has a regular hour hand and arrow minute hand. This difference is inherited from the Aqua Terra line-up, which still uses this configuration even today.


The watch is powered by the 2403 movement, which is a no date version of the cal 2500. Just like the cal 2500, due to the early issues with the co-axial escapement, the movement received an upgrade with lower beat rate. It is not a big surprise to anyone that the movement feels and winds exactly like its date sibling, the cal 2500, but without the date adjustment. Crown action is robust and very tool-watchey. The see-through case back is a nice touch and the rhodium plated movement is beautiful.

The 2504.52 is a late addition to the family. The 39mm and the 41mm versions can be found with both movement types 2403A and 2403B. However, all of the examples of the 2504.52 that I have tried to buy have been with 2403B movement with 84xxxx serial. If somebody knows whether the 36mm Railmaster came with a 2403A, I’d be interested to know and update this post.

2504.52 Seen in Wild

ReferenceSerialMovementSoldSeen onPrice
2504.5281699609??2007.1.4Yahoo Auctions Japan 17/10/2021220 000 JPY
2504.52?????Chrono24, Czech Republic4300 EUR
2504.5284699791??October 26th, 2010Chrono24, USA 24/7/20214999 USD
2504.52?????Chrono24, Singapore 11/8/20213755 USD
2504.52846979532403B2012Chrono24, Usa 6/8/20214513€
2504.5284643XXX (mine)2403BYahoo Auctions Japan 25/7/2021300000 JPY
2504.52UnknownUnknownChrono24 (Japan) 2735€
2504.528478XXXX2403BWatchuseek 30/10/20204250 USD
2504.5281699XXX2403BOmegaforums 30/8/20204150 USD
Known 2504.52 serials


The 36mm Railmaster Chronometer is an interesting watch:

  • It can be used to make a poor man’s late 00s trilogy.
  • It is an obscure alternative to Rolex Explorer.
  • It is rare and worth collecting / hunting.

Personally, I find the early co-axial movements interesting and the looks of 2504.52 appealing. It makes an excellent everyday watch and a perfect companion to the 2201.50, which I also like.

In case of errors, please reach me out with DMs. I’d like to correct them.

Omega Planet Ocean cal. 2500, 42mm


Omega Planet Ocean (PO) line was introduced in 2005. The watches come in both 45mm and 42mm size and are famous for being worn by Special Agent James Bond played by Daniel Craig. In Casino Royale, Daniel Craig wore the 45mm planet ocean on rubber strap and in Quantum of Solace the 42mm 2201.50 on steel bracelet.

Movement2500 (ETA 2892-A2)
Lug to lug48mm
Lug width20mm
MaterialStainless Steel
Water Resistance600m
Basic information

The design of the PO draws from the history of the Omega Seamaster. The PO has a two part bezel found in pre-bond Seamasters and some of the earlier Omega references. The source of the bezel design is most likely Omega Seamaster 300 ref CK2913 produced in late 1950s. Another historic design choice is the curved lugs, which omega have been using since the appearance of first ST Speedmasters.

Various References

One thing worth mentioning is that the cal 2500 Planet Ocean has sharper case than the 2531.80 or 2254.50 Seamasters. While the lugs on the 2254.50 are similar, the form is considerably softer than on the Planet Ocean. This creates an impression of quality of the finish and a more modern look. I haven’t handled a modern unpolished Speedmaster myself, but it is said that modern Speedmasters have similar quality to the lugs.

It may be that all of the 2531.80s and 2254.50s that I have handled have been polished, but at this point, it would be extremely bad luck. Until otherwise proves, I’m going to assume that the edges on the older SM300 lyre lugs weren’t as sharp as on the PO lyre lugs.

Because of the many different color combinations, strap options and sizes, the following table attempts to summarise the reference numbers for 42mm Planet Oceans:

ReferenceStrapBezel colorIndex Color
2901.50.91Stiched RubberBlackWhite
2901.51.82Rubber (orange stitches)BlackOrange
42mm Planet Ocean References

The sheer number of available references may make finding the right watch to purchase difficult. However, it is a good idea to extend one’s searches as deals can be had in any of the references. Unfortunately sometimes dodgy sellers downplay the size and offer 45mm references as 42mm and this creates further confusion.

Bracelet vs Strap

As outlined earlier, the PO came in at least four different strap configurations: steel bracelet, steel mesh, stitched rubber and rubber. I have had pleasure to handle the non-sticthed rubber, and it is easily one of the best rubber straps I have had. It is both comfortable, doesn’t have the groce vanilla smell, which connoisseurs of poverty-grade rubber straps claim to be characteristic of nice vulcanised rubber. The strap doesn’t cause itch even when worn extensively.

The bracelet for the cal 2500 Omegas is 1580 / 952. Unfortunately, my watch never came with bracelet, so until I can source one second hand, I’m unable to review it. I know that the bracelet came with both pins and screws. As with 2254.50, a popular modification is to add micro adjustment clasp to the bracelet. More of this including the parts numbers can be found in the 2254.50 article.

1580/952Original steel bracelet
1589/858Steel bracelet from cal 8500
98000144Rubber strap
98000364Rubber strap from cal 8500
Available bracelets for cal 2500

The 1589/858 sits slightly too thick on the watch, but many prefer it because of availability and better clasp. The incorrect size of the 858 end link is especially noticeable where lyre lug meets the end-link itself. The rubber strap 98000364 also extends slightly above the lugs, but it is barely noticeable.

In addition to the steel bracelet and the rubber straps, the cal 2500 Planet Ocean wears well on a shark mesh. This is one of my personal favourites because the mesh is light and comfortable. The part number for the sharkproof mesh is 020ST1380237.

Hand Winding

The hand-winding experience of the cal 2500c is very nice and smooth. Unlike the 1120 or the Rolex Calibers, you can only hear a very faint sound of turning gears when hand-winding. In many watches, I would associate this winding to the wrong direction. Once wound full, just like the 1120, the movement gives nice pleasurable clicks to tell the winder to do something more productive with their life.

2500c vs 2500d

Anyone who is looking to buy any cal 2500 Omega watch is bound to find a lot of discussion over the differences of the movement. The differences have been discussed extensively. In short, the 2500d comes with three-tier escapement as opposed to the two-tier escapement of the 2500c. It is said online that the advantage of this is that the service interval of the 2500d is longer and the 2500d movement is less subject to failure due to wear or dislocation of the part.


The biggest misconception regarding the Planet Ocean 42mm is that it is a big watch. This is most likely caused by its 45mm cousin, or the newer 43,5mm versions. The 42mm PO wears slightly smaller than the flatter 2254.50 despite being taller. It also wears considerably smaller than Seiko MM300, which feels like a chunk of steel strapped to your wrist. On my 16,5cm wrist, the watch feels perfectly balanced on the rubber strap.

The various PO strap options, the two different movement types and the three different bezels/dials configurations can make the purchase confusing and somewhat difficult. Beyond the various references, the watch has a lot to offer: not many watches are simultaneously conservative (2201.50), playful (2201.51) and slightly obnoxious (2209.51).

Fake Vietnam / Military Watch

There is a well known fake vintage watch that is persistently used to con newbies into thinking they have hit the jackpot. The dead giveaway is the reference Y22668 and the number 10589463. If you find this blog post by googling those numbers, the watch in question is a fake. None of these watches are authentic or contain a single original part.

Fake IWC

Fake IWC
IWC caseback

Fake Omega

Fake Rolex


There is a slim possibility that a legit vintage military watch exists somewhere with Y22668 and 10589463 stamped on the back. However, if Google brings you here with these numbers, the watch is most likely a fake. The brands are at least Patek Philippe, Rolex, IWC, Omega, Tudor and Breitling.

Interestingly there are few variations of the Rolex with seemingly random numbers. It may be that in later evolutions the manufacturer has switched to random numbering so that the watches aren’t easy to find by Google in blog posts such as this

Omega Seamaster Professional 300m 2254.50


This is a review about the Omega Seamaster 300 2254.50. The watch was sold along the ‘Bond’ Seamaster 2531.80 and its differences to the 2531.80 are sword hands, indices, bracelet, colors and big triangle dial. The “big triangle” on the dial along with the rectangular indices are a throwback to the classic 166.024 and 165.024 Seamasters.

Lug to lug47mm
Lug width20mm
MaterialStainless Steel
Water Resistance300m
Basic information

The distinctive features of the 2254.50 are its thinness, sword hands and speedmaster style bracelet with slight taper to the clasp.

However, to keep Omega references complex, Omega released a few other similar, but different models, such as the 2255.80 electric blue and steel, 2533.50 America’s cup with black dial and steel and the 2054.50 which nearly identical to the 2254.50, but mounted on the 5-link Bond bracelet.

Year ProductionReference NumberAppearance
19932531.80Round indices, skeleton hands, both in tritium and luminova. Black dial, blue bezel, 5-link bracelet.
19972254.50Big triangle, painted rectangular indices, sword hands. Black dial, black bezel, speedmaster bracelet.
19972054.50Big triangle, painted rectangular indices, sword hands. Black dial, black bezel, 5-link bracelet.
2255.80Big triangle, painted rectangular indices, sword hands. Blue dial, steel bezel, speedmaster bracelet.
2533.50Big triangle, applied rectangular indices, sword hands, America’s Cup printed on dial. Black dial, steel bezel, 5-link bracelet.
Table of automatic SMP300 references

Hand-winding Experience

The Omega cal 1120 derived from ETA 2824-2 is a workhorse and can be enjoyed for its utilitarian aspects. It is neither pretty or advanced, but it does the job. The advantage of the movement is that most watchmakers are able to service it.

The hand-winding experience of the 2254.50 is close to standard ETA 2824-2. There is really nothing new to anyone who has handled an ETA 2824-2. While the winding experience is quite far away from modern in-house luxury watch movements, the watch gives satisfiable clicks to notify when it has been fully wound. It also keeps excellent time.

Nato Strap

The 1610/930 bracelet of the 2254.50, even with its modest taper, is not for everyone. For a person with a smaller wrist, it can fear bulky and cumbersome. For those whose wrists swell a lot, the bracelet can be uncomfortable as it lacks micro-adjustment. The 2254.50 is a relatively thin watch and compared to the watch head the bracelet can feel big and unbalanced. Those familiar with 5-digit Rolex watches may even hate the bracelet. Luckily, not all is lost, because the 2254.50 is only 11mm thick it wears perfect on a nato strap.

Because the watch is thin, it is possible to use some of the thicker Nato straps. Similarly Nato straps with keepers, won’t feel too thick. The waffle weave Blushark Orca is a good example. Even with a 1,5mm thick waffle weave Orca, the 2254.50 is at 14mm of thickness. This is still 1,5mm thinner than a cal 8500 Planet Ocean.

My preference is to wear it on a Nato strap over the excellent Speedmaster-style bracelet. Luckily, most watches come with the bracelet, so you can decide for yourself and you won’t miss out.


ModPart number
Non-America’s Cup Dial064WZ3121001
Planet Ocean Second Hand066WZ4315
Micro adjustable claspClasp: 117STZ001154 (large)
Clasp: 117STZ004666 (small)
Sadle-link (2x): 0118ST1589
Pins (2x): 0128ST0166
Screws (4x): 0124ST3307
Mods and part numbers

Non-America’s Cup Dial: In this mod, the dial of the 2254.50 is changed to the Non-America’s Cup Dial. In this dial the indices and Omega text are applied vs painted and printed.

Planet Ocean Seconds Hand: In this mod the second hand is changed to PO seconds hand which some think fits better the sword hands. Also the tip of the seconds hand is brighter.

Micro-adjustable clasp: In this mod the normal clasp is changed to the more modern micro-adjustable clasp. This requires changing the last links to ones with screw ends. This gives the wearer three different positions to adjust the watch thorough the day.


While the movement service for the 2254.50 should be cheap, the bezel is expensive to replace. This is because the bezel will come with the whole bezel assembly instead of just insert. If one is looking for a 2254.50, it is best to find an example with excellent bezel.

The case of the 2254.50 is softer than more modern planet oceans and speedmasters. The big issue here is that the Omega lyre lugs take polishing particularly bad. A watch that has undergone improper polish is impossible to repair without a new case, so it is best to ensure that the edges of the lyre lugs are sharp.


The 2254.50 is a great watch. The bracelet and the bezel action of the 2254.50 is a letdown. The size, sword hands, lume and dial make up for its downfalls. People who suffer from swollen hands should definitely look into the micro-adjustment mod. The watch is simply great and works well with bracelet and even better on a Nato strap.


  • Size
  • Serviceability
  • Sword hands
  • Lume


  • Bracelet is heavy and tapers only slightly. Micro adjustment is minimal and depends on half-links.
  • Bezel action

The most notable characteristic of this watch are its thinness and sword hands. People who prefer wrist presence are going to enjoy the more modern Seamasters or Planet Oceans. Either way, so far this is the only modern watch in the Seamaster line up with the sword hands, which makes it favourite to some watch collectors.