
Wristwatches · Wristwatch
Omega Seamaster 300 ref. 165.024, 'Big Triangle' Military Issued with Extensive Documentation
- Maker / attribution
- Omega (maker)
- Date
- c. 1968
- Historical period
- Modern Mechanical Horology (1945 – 1969)
- Country of origin
- Switzerland
- Object type
- Wristwatch
- Stock no.
- OC2945
- Credit line
- Dealer listing, Oliver & Clarke (OC2945)
- Catalogue title (original)
- Omega Seamaster 300 Ref. 165.024 - 'Big Triangle' Military Issued w/ Extensive Documentation (English)
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Record summary
Catalogued by Oliver & Clarke (dealer), United Kingdom (stock number OC2945), this is a wristwatch by Omega, made in Switzerland, dated c. 1968. The Atlas places it in the Modern Mechanical Horology period (1945 – 1969) of its Wristwatches collection. The record is illustrated with 6 photographs.
Assembled from the source record's structured fields. Dates and attributions are given as the source states them; where a field is missing the Atlas leaves it blank rather than estimating.
Catalogue description
Dealer description — Oliver & Clarke
The Omega Speedmaster is one of the most historically important, if not the most important wrist watch ever produced, full stop. Its story can be summed up with one simple acronym: NASA. Surely, this is not a watch that needs an introduction with our audience... However, the sibling to the Speedmaster, the Seamaster, is worth shedding some light on. The model family was conceived in 1948 as what was effectively a time-only watch, not the dive watch that is most commonly associated with the named today. It wasn't until nearly a decade later where the Seamaster 300 would show up with its rotating timing bezel and larger case size. As with so many other icons and popular vintage models, the Seamaster has seen countless iterations and variants over its nearly 70-years of continuous production, but it is the 300 that is probably what comes to mind when you hear the name. The piece that we have here today is indeed a Seamaster 300, but not just any Seamster 300... This Reference 165.024 not only possesses a few small details that collectors actively search for (more on those later), but is also a military-issued example from the late 1960s. Around this time, the British Military had the need for a dive watch that could meet their specific needs and specifications, and Omega's Seamaster 300 was chosen as a starting point. The design would be modified only slightly to have a 'fixed'-bar lugs. Depending on whether the timepiece was issued to theArmy or Navy, the dials would bear a 'circle T' stamp on the dial denoting the presence of Tritium. This piece bears one of those dials. Dating to circa 1968, this piece is offered in strong condition given its past history. The 'twisted'-lug case remains thick, with both brushed and polished finishing throughout and of course has those 'fixed' bars to accommodate a NATO-style strap. The crown is a correct signed screw-down unit (earlier examples did not screw-down). Even the bezel assembly and the black acrylic insert remains in great overall condition, with no apparent fractures or major damage — just normal wear. The Tritium within the insert also shows up evenly under UV in relation to the dial and handset. The dial, in additional to the highly desirable 'circle T' also features what collectors call a 'big triangle' at the 12 o'clock position and is devoid of the date complication at the 3 o'clock position for perfect dial symmetry. The matte black surface is exceptionally well-preserved, with very attractive and evenly patinated indices throughout. The handset matches the dial nicely and is of the 'sword' style, which would later be a requirement for the British military in future issued watches from other brands. Flip it over, and you'll find those military issue caseback engravings. Inside, Omega's automatic-winding Calibre .552 workhorse movement powers this piece. This piece, on its own, would be a treasure, a real piece of horological history. But it gets better! Accompanying this piece is extensive documentation pertaining to its military provenance. On top of an extract from Omega confirming production of the watch in 1968 and delivery to the British Army, we have copies of the certificate of service of its original user, copies of photos of the individual, and a hand-written letter from the son of the original recipient. An absolutely fantastic package. Not only is this a piece of history, but when compared to other military-issued pieces from other brands, this actually is fantastic value, and they sure don't grow on trees.
Historical context
Modern Mechanical Horology (1945 – 1969)
Tool watches for divers, pilots and astronauts; electric watches anticipate the electronic age.
The classic era of the mechanical wristwatch: dive watches, chronographs for motor racing and space flight, GMT watches for jet travel, slim dress watches, automatic calendars, and the rise of Japanese manufacturers alongside Swiss, American, German and Soviet industries.
Read the period in the timelineMore wristwatches from this periodEarlier: Golden Age of Mechanical Watchmaking
Atlas type guide
Dive and water-resistant watches
Keeping water and dust out of a wristwatch was a long-standing challenge. Rolex's screw-down Oyster case (1926) and Omega's Marine (1932) were landmarks; in the early 1950s Blancpain's Fifty Fathoms and Rolex's Submariner defined the professional dive watch with rotating bezels for timing dives, luminous dials and high water resistance. The ISO 6425 standard (1982) later codified what a 'diver's watch' must do.
Dive watches became icons of post-war design and exploration, and their evolution — helium escape valves, ceramic bezels, saturation-diving depth ratings — records the history of underwater work.
What to look for
- Unidirectional or bidirectional rotating bezel with minute markings.
- Screw-down crown and case back; depth rating printed on the dial.
- Luminous hands and markers (radium before c. 1960, tritium c. 1960–1998, then Super-LumiNova).
- Reference numbers on the case between the lugs or inside the back.
Dating clues
- Screw-down Oyster cases: from 1926.
- Professional dive watches: from 1953.
- Tritium 'T' marks on dials: c. 1960–1998.
General guidance written by the Atlas editors about this kind of object. It is not a statement about this particular piece; for that, rely on the source record above and on physical examination.
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