Introduced in 1957 alongside the Speedmaster and Railmaster, the Seamaster 300 established Omega’s purpose-built dive watch and became one of the defining professional watches of the company’s post-war era. By the mid-1960s, the design had evolved considerably, gaining the twisted “lyre” lugs, broader bezel and larger case that collectors now associate with the second generation of the Seamaster 300. Reference 166.024 added a date display to this formula, distinguishing it from the otherwise closely related no-date ref. 165.024 and creating one of the most recognisable vintage Seamaster configurations.

Dating to 1967, this example features the highly desirable dial configuration known to collectors as the “Big Triangle”, named for the oversized luminous triangle at 12 o’clock. The design is closely associated with the military character of the Seamaster 300 and was developed for enhanced legibility, including watches supplied for British military use. Here it is combined with the broad sword handset, black rotating bezel and date aperture at three o’clock, creating one of the most recognisable vintage Seamaster configurations. Inside is Omega’s automatic calibre 565, while the watch is fitted with a desirable period ref. 1039 flat-link bracelet stamped 4/68 with ref. 516 end links.

Watch is in overall excellent condition. The stainless steel case shows surface scratches and small nicks. The case back retains well-defined engravings and shows some surface scratches. The bezel and insert remain in excellent condition, with some surface scuffs. The dial is in excellent condition, with darkened hour markers and some small surface marks. The hour and minute hands appear to have been relumed, while the white seconds hand has a crack in the luminous material. The acrylic crystal shows some surface scuffs. It is fitted with a stainless steel flat-link reference 1039 bracelet with clasp stamped 4/68 and reference 516 end links, showing surface marks and light play between the links. The bracelet is fitted with 23 links and fits approximately a 7¾” wrist.

Please note: The watch ticks at time of cataloging, but timekeeping is poor and a service is recommended.

Among vintage Seamaster 300s, the “Big Triangle” has become one of the most immediately recognisable and desirable configurations. The oversized 12 o’clock marker and broad sword hands give the watch the purposeful, military-influenced appearance for which these examples are particularly prized, while the date-equipped ref. 166.024 adds everyday practicality.