Omega Ploprof Seamaster 600 - The Instrument Watch of Professional Divers

Jul 04, 2020,15:02 PM

Issued by Omega, Sales Promotion, Bienne.

Omega Master Waterproofness with the SEAMASTER 600

The Instrument Watch of  Professional Divers

Watchmakers have always been occupied by the problem of water- proofness. Water, vapours, dust and volatile chemical agents arc cunning and formidable enemies of a watch. We have solved this problem, and our waterproof models are perfectly safe for normal everyday use.


However, other qualities than normal waterproofness are needed in watches for serious underwater work and underwater sport. Skin - and SCUBA - diving are both rapidly growing in popularity. Now, no-one takes deep-sea diving lightly; the deeper you go, the more pressure you are under. And this same pressure is felt by your watch, so it must be absolutely waterproof. It must indicate exactly how much time the diver has left, without the need for manipula­tions and complicated calculations. It must be clear enough for the diver to check his decompression stages accurately, and it must be luminous enough for the darkness of the deeps. Finally, it must be tough enough to stand up to bumps and bangs that would throw a lesser watch off balance.

All these qualities can be found in the Seamasters 120 and 300; both were built to last, built to play a vital role, and built to take anything the amateur diver could hand out to them.


'Die exploration and exploitation of the sea has begun in earnest. The untold riches of the oceans are attracting international enter­prises, and with them professional divers; divers who need equip­ment of absolute and guaranteed reliability. The last simulated caisson experiment made it possible for men to live at minus 1,500 ft, and foreshadows exploits which in daring and value will equal those of the astronauts.

And so, to complete and crown the Seamaster range we developed the 600, the most highly perfected and reliable watch for profes­sional divers.


Perfecting the 600 was a long and costly procedure. Years of re­search, the help and advice of specialists, public relations efforts in professional quarters, all went into the 600. Our prototypes have taken part in experimental diving tests to 1,800 ft in helium and 750 ft under water. They are being used at present in all the great experiments, especially those of COMEX; the last of which, Operation “Janus”, was resoundingly successful.


In the conception of the 600, we left nothing to chance. Every risk was calculated, and the slightest details were minutely considered, so as to give the new Seamaster maximum reliability.

Our technical department has specially adapted a helium leak de­tector for intensive tests of the 600’s waterproof qualities. The results of these tests were absolutely conclusive. We use helium because this gas has an infinitely greater penetration than either water or air. The helium molecule is thirteen times smaller than a molecule of air, so that if a watch is helium-proof, that is a gua­rantee of absolute waterproofness.

Therefore, the use of a helium leak detector amounts to a virtual guarantee for the 600.

Helium leak detector

-      the helium leak detector checks on waterproofness.

-      helium penetrates across a constant magnetic field, checked by a mass spectrometer.

-      a pressure-reducing manometer makes observation possible to 100 atmospheres (3,000 ft)

-      even the most minute leak can be charted.

Let us put it this way; if a Seamaster 600 was tested to the equi­valent of 1,800 feet, it would take 1,200 years to fill with helium !

Testing to 3,000 ft a watch which will not be used at more than 1,800 gives a margin of safety which illustrates our conscientious, professional approach, and which will be of great value in our ad­vertising.

We should mention here that the depth of 1,800 ft could only be reached in a bathyscape, with a helium atmosphere. Outside a bathyscape, for amateur or semi-professional divers the limit is 270 ft, which highlights the outstanding waterproofness of the 600.

The case is mono-bloc, of special steel, ultra-resistant to shock and salt water corrosion. The back is grooved, so as not to slip on the wrist. The design of the case, with a promontory to protect the crown, gives the watch a kind of functional beauty. The red push- piece is an indication of its advanced techniques.

The crystal is of mineral glass, chemically tempered by a treatment which ensures the best possible distribution of the hard coating, and improves its stability. The glass is anti-reflective and anti-abrasive. The crystal is surrounded by a super-compressed “O’* ring, so that the pressure exerted on the joint is always greater than the hydro­static pressure. The case and crystal are thus hermetically sealed against any infiltration.

The crown has three positions : for winding, setting the time and setting the date. During this last, the movement stops, so the hands can be set to the second. Unlike ordinary watches, the crown is placed at 9 o’clock, thus allowing the wrist greater freedom of movement. It is built into the case so that there is no risk of snag­ging. The crown is locked by a safety device, and a patented twin- lock system assures it of perfect waterproofness. The turning bezel, graduated from 0 to 60, is protected by a locking system governed by the red push-button. The graduations and numerals of the bezel are highly luminous, for greater safety. The bezel has a triangular guide mark, which is set opposite the minute hand at the start of a dive. Thus elapsed time can be quickly and easily read off.

The movement. For the Seamaster 600 we have adopted the calibre 1000. This high-frequency, self-winding movement is eminently sui­table for a diving watch. It gives the diver additional security, as he does not have to remember to wind the watch.

The calendar has an instant corrector, and the date changes auto­matically.

High luminosity. The bezel, hands and dial are treated with tritium for greater luminosity at depth. The oversized minute hand adds to legibility, and the bezel is outside the watch, to leave the dial free. Confusion between the bezel and the minute markings on the dial is impossible.

Ultra-durable bracelet. After intensive research, we chose a truly exceptional material for the bracelet : Isofrane. This synthetic ma­terial has unique physical and chemical characteristics. It is resis­tant to tearing, deterioration, abrasion, temperature fluctuation and corrosion. It keeps its shape, does not cause allergies, and is very light. It can easily be delivered in larger sizes, when the watch is to be worn over a diving suit.




The Seamaster 600 is the surest watch for the men who work on the seabed. Already it has a great reputation. Soon it will be talked about even more, like the Speedmaster, and will profit from the fame of the whole Seamaster range.

Naturally, the number of buyers who are real professionals will be small; but the potential of the watch among amateurs is enormous. Like the Speedmaster, it will benefit from the exploits associated with it, and like the Speedmaster it will be worn by numbers of people who do not at all need an instrument watch. These consi­derations seem to us to justify an initial manufacture of 4,500 watches.

The Seamaster 600 is a lead product which fits perfectly into our general policy; that of leading every field of timekeeping.After the heights of space, we are about to conquer a new empire; that of the deeps.

*Source original press release from the 1970's

More posts: 16660168055135514ComexDiverPloprofSea DwellerSeamasterSeamaster 600SpeedmasterSubmarinerSubmariner Date

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Comments: view entire thread


A piece of history ...

 By: nilomis : November 3rd, 2013-12:37
Thank you, Bill for sharing this detailed document about the Ploprof. For no personal reason (I don't dive) I admire all dive watches and the brands quest to conquer the deeps. Years back I took pics of this model and it wears very nice, despite the very ... 

Was price really the issue???

 By: Bill : November 3rd, 2013-17:17
"waterproofness" - The race was on to conquer the deep between Rolex, Omega and even Doxa in late 1968 - 1969 period. While it is true that the Omega Seamaster 600 "Ploprof" was the technology leader it was rumored that their price point was double that o...  

So what do you think about the lack of early success

 By: Bill : November 4th, 2013-07:05
Was it price in the market. Or was the design too avant garde. Bill

Thank you, Bill!

 By: blomman Mr Blue : November 4th, 2013-13:41
This is great information. Thank you! Best, my friend Blomman

I reproduced it faithfully

 By: Bill : November 4th, 2013-14:08
All the pictures and text are as they were in the original press release. Best Bill

Very informative!

 By: Hagen : November 6th, 2013-17:32
Thanks, Bill, for posting this. I must admit not really being a Ploprof fan, mainly because of the size and thickness. Not to mention the fact that I am not a professional diver. However, when I read the article you post, it gives a new perspective. I rec... 

That is the beauty of collecting

 By: Bill : November 6th, 2013-19:13
Our tastes change and evolve over time and we start to get different pleasure that we otherwise did not get in the past like fine wines. The Ploprof is a great example of technology that was mastered but due to reasons unknown (design / style) it was left... 

Glad to see this thread resurrected! Two comments to add . . .

 By: Dr No : July 4th, 2020-14:40
. . . to the discussion: first, your observation regarding the Ploprof's suitability for smaller wrists is on the money. It's a wide and thick design, which normally doesn't bode well for the wrist-challenged. The asymmetrical case and sloping bezel are t...  

Interesting perspective on this subject Art ...

 By: Cpt Scarlet : July 5th, 2020-12:47
Especially the issue of left-handed versions.


 By: Weems@8 : July 5th, 2020-14:45
An orange Ploprof. For me a king. Holy moly, it is a watch i wil catch if it cross my path. How it wil be fit on my wrist? It’s a gamble. 🎲

The quartz crisis/Omega Planet Ocean/Doxa etc.

 By: Weems@8 : July 5th, 2020-14:35
You say it right. When Doxa put quartz calibers in it’s cases to fight against quartz opponents. It hurts Omega. The ploprof has become a cult classic, while the quartz equipped dive watches are not wanted. The space race and the depth race. I think the d... 

Bump [nt]

 By: Bill : July 4th, 2020-08:30

Hi Bill ..

 By: Cpt Scarlet : July 4th, 2020-16:08
I think the answer is down to design. Back in the day the Ploprof 600 had the technical edge for professional divers. This was a a huge watch in the 70s and regarded as more of a technical instrument than purely a wrist watch. Thanks for posting this fasc... 

" . . . more of a technical instrument . . .

 By: Dr No : July 4th, 2020-16:27
. . . than purely a wrist watch" - truer words never said. Same goes for its contemporary, the Flightmaster . . .

I completely agree Art ...

 By: Cpt Scarlet : July 4th, 2020-16:41
The two manufacturers had different views of what constituted technical ability and the Flightmaster is part of this history.

Better times? . . .

 By: Dr No : July 4th, 2020-17:34
. . . I'll say. Try doing this . . . . . . today. This clip is well worth watching . . . . . . if you can remember the old days, and essential if you can't. Art

Retro cool

 By: Cookies : July 5th, 2020-05:26
Nice post Bill

Superb write up dear Bill

 By: Seeks : July 5th, 2020-08:27
I learnt a lot. Thanks for bumping it up!

Late to the party, but a big fan. Thanks so much for all this digging. So interesting to read this history. Brings back a sweet memory of my first visit to a major, big-city AD, in

 By: halgedahl : July 5th, 2020-09:42
San Francisco. Had a long list of pieces I was interested in seeing—Omegas notably absent from the list. But my flight was cancelled next morning, so back I went, for another afternoon of ogling. Of course there was a large Omega section—the largest in th...  

Highly beloved Omega

 By: Weems@8 : July 5th, 2020-14:51
Never to late at the party. Discovering Omega is like walking into space. I enjoy the F.P. Journe journey, and Omega is running up to become a next beloved subject for many here. What Omega makes so special, it put all boundaries to next levels.

For Seamaster fans

 By: Weems@8 : July 5th, 2020-14:23
For sure, i become a Seamaster fan. The ploprof is an interesting Omega. The first 600. The picture in the advert have that Jaques Cousteau era style. I watched many documentaries about Jaques Cousteau ocean discoveries. I like scuba diving, and i must in... 

thanks for sharing it [nt]

 By: Passionata_george : July 6th, 2020-12:30