Omega Seamaster 1000 166.093

A CollectΩr's Guide

Begin the journey


The purpose of this website is to assist the avid collector in pursuit of what is one of the rarest Seamasters ever produced. The was model number 166.093 and was nicknamed ‘The Grand’ by virtue of its 1000 metre rating.

This watch had an extremely limited production split into two iterations. The first iteration in 1972, with a 1002 calibre, had fewer than 150 watches made. The 2nd iteration in 1976 in the 1012 calibre had possibly 300 watches produced.

With a total run speculated as being fewer than 500, a significant proportion of the watches in circulation today are either copies or made up of service parts.

The watch has been seen with the following –

  • 3 bezel types
  • 2 bracelets
  • 2 cases
  • 4 dial types
  • 4 hour hands
  • 2 movements

It needs to be appreciated that the study of vintage watches is always the study of probability as today’s accurate production methods were not those used 40 years ago.

Additionally, prior to the advent of the computers, record keeping was subject to its own idiosyncrasies and variabilities.

What the author has tried to do in establishing the true heritage of this watch, is to sift through many many hundreds of documents, records, explanations, descriptions, commentaries, images, movement numbers and watches to come to what is effectively a consensus …..and thus this study should never be used dogmatically.


During the early years of working with COMEX, innovation in saturation diving gave rise to the requirement to produce a more waterproof deep sea watch than the existing Seamaster 300. So the engineers at Omega merged a monocoque front-loaded case with the newly developed 1000 calibre series, giving birth to the Seamster 1000.

Omega was at the forefront of early years of research and development of deep-sea watches and saturation diving and were the exclusive supplier of COMEX up until 1971.

The 1000 metre watch had a simple rotary time-lapse bezel and the engineers designed a watch that was so waterproof and air-tight it would not require a helium release valve.

The new prototype showed more similarity to the existing house style by using the famous pilot-line style case as exemplified in the cosmic 2000 range (see cases below).

In addition, it used the slimline 1002-1012 automatic movement with the high-visibility minute hand plongeur set and a new innovative one-way rotary time-elapse bezel.

The 1000 has a 0.5cm thick crystal and it was repeatedly “top to bottom” tested (Omega used barometric chambers and subjected the watches to pressure cycling equivalent to taking the watch to the “top of Everest and to the bottom of the ocean”). Independent evaluations of the watch pronounced it more water-tight than a submarine and impervious to the helium ingress problem.

The Seamaster 1000 was tested alongside the Seamaster 600 and was attached to the International Underwater Contractors submarine “Beaver Mark IV” to measure the effects on the crystal at a depth of 1000 meters and more.

Further testing was carried out by Richard Winchester at Intersub at depths to 1000m. His prototype watch 101 can be seen in the photo on the left and a close up below.

A prototype of the Seamaster 1000 using the 552 calibre Seamaster 300 movement, which was produced in 1967-68 and was delivered to COMEX in mid 68 to be used in on-shore saturation diving tests and to be used in Hydra 1.

This watch was the precursor of the Seamaster 600 not the other way around.

The bezel numbers are taken from the US Navy decompression table.

Note the small centre seconds hand which is there to show the watch is working and the enlarged high-visibility minute hand. This was an incredibly successful watch very well received by all the divers and by COMEX.

First registered design of the watch; post-production but prior to retail sale.

1974 prototype series 3-1xx

Movement number 33110xxx showing the right-hand configuration, type 1 bezel but using the Seamaster 600 type 3 dial.

1975 Prototype series 5-0xx, 5-1xx and 5-2xx

The prototype 5 added for the first time the redesigned Beyeler dial, which reflected the new position of the watch in the Omega hierarchy and its new depth.

This is the legendary prototype tested by Intersub on behalf of Omega at 1000m on the outside of a submarine piloted by Captain Dick Winchester in 1975.

This watch carries a pre-production prototype dial is using a spear second hand and has a special chronometer-rated 1011 movement, issued prior to the 1012. This watch was used to calibrate temperature/time variations to determine the effect of sub-zero/icy conditions on the time-keeping accuracy of the watch.


Prototype watch used by Nasa flight surgeon Dr Edward Beckman whilst researching the effect of deep-sea pressure on the human anatomy in Sealab 1, 2 and 3. Unfortunately the dial has been changed (see the original at Dials).

Correct dial, correct bezel, serviced hands, built with a right-hand crown issued on or around 1975.

Prototypes with even numbers 2 and 4 were allocated to the Seamaster 600, whereas odd numbers were allocated to the Seamaster 1000.

It is most likely that entire prototype population was in the order of a maximum of 100.

The Grand was no longer sold after 1982 but Omega undertook the development of an electronic version.

1982 Electronic Prototype Series

F300, based on the 1250 calibre Mosaba (movement sans balance) Chrono most likely the 1972 1260 calibre in this model

This utilised the bulova-licenced tuning fork technology and is technically identical to other F300s in the Omega range, however, it utilised a heavier case, new plongeur handset and The Grand rotary time-elapse bezel.

The reason for its rejection was never clear but it’s suspected that cold water gave rise to high battery consumption and the requirement for regular battery changes probably didn’t sit well with professional underwater divers.

A very advanced innovation using the new megaquartz 1510 base movement, however, the megaquartzes were not thermo-compensated and in a cold water environment, they could lose significant amounts of time. In addition battery life was also a problem.

Seamaster 1000 T1 Prototype Titanium (1982) based on the 1110 calibre, most probably the later version, possibly the 1111. Reputedly made subject to a tryout for the French Navy but rejected due to expense.

The Watch


These were an acrylic-based plastic, which were often subject to damage and cracking and because tritium paint, used on the markers, was hygroscopic the bezels often suffered from extensive damage once water penetration occurred.

There appear to be three bezel variations.

The tritium on the B1 and B2 bezels patinates to a caramel colour. The markers under the 10min point are pentagon-shaped.

The B3 Bezel luminova does not patinate and remains the same colour throughout. The markers under the 10min points are triangular.

B1 Bezel

This is only seen on prototypes.

  • seriffed ‘1’ of the ’10’ marker
  • Round topped ‘3’ of the ’30’ marker
  • 10 minute markers missing
  • coloured in triangle

B2 Bezel

This has the identical insert to the Seamaster 600 B1 bezel –

  • straight ‘1’ of the ’10’ marker
  • thin line triangle marker
  • stylised lower half of the ‘2’ of the ’20’ marker
  • flat topped ‘3’ of the ’30’ marker
  • pentagon 10 minute markers

B3 Bezel

The modern service bezel insert is similar to the Seamaster 600 B5 –

  • seriffed ‘1’ of the ’10’ marker
  • simpler lower half of the ‘2’ of the ’20’ marker
  • Round topped ‘3’ of the ’30’ marker
  • flat topped ‘4’ of the ’40’ marker
  • smaller thick-lined triangle
  • triangular 10 minute markers


The edges shown in comparison side by side against a Seamaster 600.



The Seamaster 1000 was the first watch to be standard issued with the 1970s newly created milanese bracelet and it comes in two varieties with two extenders.

The bracelet is properly described as the “Omega Shark” bracelet petit maillese with slipping clasp. This bracelet later appeared on 3rd and 4th generation Seamaster 600s but it was standard issue on the Seamaster 1000 from the outset.

Next to the standard strap buckle can be seen an early prototype Omega buckle with no internal length adjusters. It was only to be issued to professional divers who used the rubber extension and/or the metal extension as seen in the picture.


A reference often found on a prototype strap.

Service bracelet

The original bracelet is a 1247-237 with a circled ’37’. This is of very generous length and rarely requires the metal insert and has a low-shine finish and was manufactured by SP.

The service bracelet is a 1247-237 with a circled ’59’, which is significantly shorter with a high-shine chrome-like finish.

There are also two different manufacturers of the service bracelet being IAI and JJF.





All cases were and are built with the right-hand crown lining up with the internal inscription.

When assembled for the retail market and whilst prototype tested, the movement was installed with the case upside down to make the watch more comfortable by positioning the crown on the left-hand side.

This causes some confusion within the collector community and this is a welcome opportunity to disabuse the so-called experts on this issue. Even the modern copy cases are right-hand crown configured but left-hand crown assembled.

5th generation prototype. Right-hand crown.

This monocoque-style case from the Seamaster ‘Cosmic’ range when added to the flightmaster front from 1969 was clearly the influence for the eventual production case.

Early watches had a grooved non-slip flat back and were based on the then available calibre 1002 with date and this was modified into the ultimate retail-configuration with the crown on the left assembly and gentle curvature on the case back making for a very comfortable fit.

Early prototype. Flat back.

There are 2 primary style watch cases – the original case and copy cases. Externally they are identifiable by the case finishes and the shape of the lugs.

The manufacturer of these cases were Ervin Piquerez SA, known as EPSA, their signature mark is the diving bell and in copy cases these diving bells are clearly disproportioned as well as having issues with the font.

Internally the original and copy cases can be identified by the style and type of printing and by the font particularly in respect of the letter A.

Because of the substantial damage sustained by cases when used by professional divers, Omega was compelled to produce a series of service cases some of which found their way into the hands of external suppliers (see copies).

It has recently been proven that a third case style may potentially exist as the 1012 calibre will not sit in a 1002 case as the rotor of the 1012 comes into contact with the small available space.


When the watch was in prototype and pre-production form the manufacturer chosen for the dials was Beyeler. This was the same manufacturer who was contracted to make the Seamaster 600 dials and was well known for making dive watch dials for other manufacturers such as Rolex. In the initial stages the chosen dial was that of the Seamaster 600 and even in its pre and post-production phases, it retained the Seamaster 600 part number 1427.

When the calibre was switched to the 1012 the watch was re-rated and the new depth of 1000 metres was put on the dial in replacement of the previous 600, giving the watch its title.

There are three dial types. The dials were blue of various shades and were invariably affected by a crystallisation which caused bubbling around the pinion hole and on the surface of the dial.

When moist air became trapped in the case the tritium dial markers would go black or stained because of mould.


Bubble Dials

Because the watch was air-tight moist air inside the watch would be trapped thereby allowing a corrosive interaction to occur between the brass dial base and the organic paint being used.

This produced the dial “bubble effect” with which a large number of watches were afflicted.



The hands were of the plongeur style by and large the same as the Seamaster 600 however the hour hand had four variations.



The watch was originally fitted with the calibre 1002 movement but was later changed to the vastly superior 1012 for use in type 5 prototypes and that remained in the watch for retail sale.

The 1000 movement has occurred in a few prototypes from early 1968 – 1971


The 1012 prototype movement on or around 1973/74


The image above shows the movement used in the 75 prototypes and beyond into the commercially available watch.

As was often the case; entire movements were exchanged at service as it was not possible to use a 1012 upgrade to replace a 1002 movement because the internal case dimensions were different. It is possible to date an early case by its calibre and by its dimensions.

It is generally accepted that the range for the 1012 calibre watches available for retail sale in 1976 through to late 1977 were on or around the 38million serial number.


Mystery of the Missing Watches

At the current time, there are enquiries being carried out by the Author to find out what happened to the pre-production 1002 calibre watches.

With the help of Alejandro, Juan and Pablo, Venezuelan watch collectors, the Author has found a cache of 10 watches in Venezuela allegedly sold in the early 70s, all with D1/D2 Seamaster 600 dials. At the time Venezuela was the 8th largest economy in the world and a very important market for both Omega and Rolex.

The authorised distributor Salvador Cupello sold this small batch of pre-production 1002 watches to VIPs and prominent local collectors.

These watches are not part of the “Raineir” public-issue watches made by Omega. There were probably less than 150 watches made, with 50 watches allegedly going to Prince Rainier.

Despite extensive enquiries by the author most if not all the Venezuelan watches appear to be dial swap cases.

This site is still a work in progress and will be updated to reflect new discoveries.


Because of a surplus of service cases watchmakers were able to rapidly recreate similar copies of this iconic watch. These copies are usually easily identifiable using the guide above. They most often contain the cheaper 1002 movement with the service dial, bezel and hands. Any watch that looks too good to be true most probably is.

Price & Value

Very difficult to accurately price this model because so few of them come up for sale. Even the “copies” made up of service parts regularly sell for close to £5,000.

A starting price for this watch in original condition is in the order of £10,000 -£17,000

The top price for a watch with a prototype or interesting heritage guided by recent Seamaster 600 sales will be in the order of £30,000+ at auction.

There is no accurate estimate for production, it was marketed properly for 2 years from 1976 and the last one was delivered in 1982 but was usually only ever bought by professional divers.

Examination and empirical evidence suggest that production is likely less than 500 and this combined with the high attrition rate means that there are probably fewer than 300 reasonable examples still available and the 1972 1002 version is even rarer.

It should be noted that the price of these watches have begun to rise rapidly since the creation of this guide and people have become aware of this incredible watches provenance.

If you are uncertain as to the value of your watch it’s completely free

please contact the Author on

In Review

Firstly this whole work is free to read, and please use it and quote from it without inhibition, but a small favour I would ask would be to give attribution when copied so that others may be lead to the source

It’s worth mentioning that this is an ongoing work. The more info provided by the collector community at large the more we can refine and perfect this and future websites

I am attempting to crowd-source as much as I can about other specialisations in review at the moment, so if you found the above helpful please contact me regarding –


About The Author

This website was created by a former adjunct academic and collector for over 50 years.

In order not to hamper his research he prefers to remain anonymous
however he can be found on Instagram @t_solo_t.

He’s happy to be emailed for all or any questions at

Sincere Thanks

Particular thanks the helpful staff of the Omega Museum. To an enthusiastic and knowledgeable American collector who has kindly provided rare prototype images.

This site is dedicated to ANDREA and MARTINA Rosie, Jake, Bella and Bear.