Omega Seamaster 300 Automatic 2551.80 36mm 1990s

Omega Seamaster 300 Automatic 2551.80

Introduction

Produced between circa 1996 and 2006, the Omega Seamaster 300M reference 2551.80 is the mid-size automatic version of the blue-dial Seamaster Professional that defined Omega’s resurgence during the 1990s. It shared the same engineering and movement as the larger 2531.80 but in a 36.25 mm case, offering the full specification of a professional diver in a more compact size. Powered by the chronometer-certified calibre 1120, it maintained Omega’s reputation for precision while presenting a design language that became instantly recognisable through its scalloped bezel, skeleton hands, and wave-pattern dial. Though eventually replaced by the co-axial mid-size 2222.80, the 2551.80 remains one of the most balanced and wearable watches of its generation.

The 1990s Seamaster Revival

Omega’s 1993 relaunch of the Seamaster 300M marked a turning point for the brand. Moving away from the integrated bracelet styles of the 1980s, the company returned to producing functional, professional-grade dive watches that could hold their own against anything from Rolex or Breitling. The combination of practical design, refined finishing, and accessible pricing helped re-establish Omega’s position in the sports watch category.

Within this new lineup, the 2551.80 served as the automatic mid-size variant. It provided an alternative for those who admired the design of the full-size Seamaster 2531.80 but preferred subtler proportions. Alongside it sat the quartz-powered 2561.80, which visually appeared identical but catered to those prioritising convenience. All three shared the same 300-metre depth rating, helium-escape valve, and iconic five-link “Bond” bracelet.

Case and Proportions

Compact but Capable

The case of the 2551.80 measures approximately 36.25 mm in diameter and a little over 11 mm thick. It wears lower than expected thanks to Omega’s slim automatic calibre and contoured lugs that ensure a close wrist fit. The lug-to-lug span of around 44 mm gives the watch a natural balance, suitable for a wide range of wrists.

The 18 mm lug width allows for numerous strap options, though the factory bracelet remains the most authentic pairing. The case finish alternates between brushed surfaces on the upper planes and polished bevels along the lugs, creating subtle highlights under changing light. A screw-down crown at 3 o’clock, protected by solid crown guards, ensures water resistance, while the manually operated helium-escape valve at 10 o’clock underscores the professional diving credentials.

Bezel and Crystal

The unidirectional bezel features the familiar scalloped edge, providing easy grip even with gloves. Its aluminium insert is coloured in deep blue, matching the dial tone, and is marked by a silver dive scale with a luminous dot at zero. The bezel action is sharp and precise, offering 120 clicks with reassuring resistance.

Covering the dial is a domed sapphire crystal treated with anti-reflective coating. It sits slightly proud of the bezel, helping light play across the wave dial. This small design detail gives the watch added depth and dimension, particularly when viewed at an angle.

Dial and Hands

The Wave Motif

The blue dial is perhaps the most defining feature of the 2551.80. The engraved wave pattern adds both texture and character, making the watch instantly recognisable even from across a room. On the smaller dial surface of the mid-size model, the pattern appears slightly tighter and denser, enhancing visual complexity without compromising legibility.

Polished, applied indices filled with luminous compound mark the hours, and the skeletonised sword-style hands are filled with matching lume. The white seconds hand features a luminous lollipop tip, a design cue that has become a hallmark of the Seamaster Professional series. Early versions used tritium lume, which can age to a warm creamy hue, while later examples transitioned to Super-LumiNova for longer-lasting glow and stability.

Clean Layout and Balanced Design

The date window at 3 o’clock is neatly integrated, using a white date wheel for contrast. Omega made a small but deliberate design choice on the mid-size model by removing the half-hour marker beside the date aperture, giving the display a cleaner, more symmetrical look. The printed text is consistent with other pre-co-axial models: Omega’s applied logo and wordmark at 12, “Seamaster Professional Chronometer” at the centre, and “300 m / 1000 ft” above 6.

Movement: Omega Calibre 1120

Technical Precision

At the heart of the 2551.80 lies the Omega calibre 1120, based on the ETA 2892-A2 but heavily modified and chronometer-certified by Omega. This movement runs at 28,800 vibrations per hour and features 23 jewels with a power reserve of around 44 hours. The 1120 is appreciated for its slim profile, efficient automatic winding, and consistent timekeeping.

The finishing includes rhodium plating and Geneva stripes on the rotor, showing that Omega treated even its non-display back calibres with respect. Its thin architecture allows the watch to maintain an elegant case height uncommon for dive watches of this depth rating. Many collectors still regard the 1120 as one of Omega’s finest pre-co-axial calibres, combining proven reliability with understated refinement.

Mechanical Character

In daily wear, the 1120 feels smooth both in winding and on the wrist. Its quiet rotor and responsive crown make it practical for long-term use. Accuracy remains impressive even decades after production, provided it receives proper maintenance. This was the movement that re-established Omega’s mechanical credibility before the brand’s eventual adoption of the co-axial escapement.

Comparing Mid-Size and Full-Size Models

The 2551.80’s 36.25 mm case is often described as the ideal balance between sportiness and elegance. It wears smaller than the 41 mm full-size 2531.80 but retains identical specifications: the same 300-metre depth rating, helium-escape valve, and chronometer-certified movement. This parity is notable because many brands historically reduced technical capability in smaller cases. Omega’s decision to maintain full performance across both sizes highlights the company’s commitment to functional integrity.

On the wrist, the mid-size offers a more discreet profile. The absence of the half-index near the date window and the tighter wave pattern on the dial subtly differentiate it from the larger version. For many, it achieves the ideal proportion for daily wear, combining versatility with unmistakable Seamaster identity.

Historical Position and Evolution

The 2551.80 occupies an important place in Omega’s timeline. It was produced during a decade when the brand was rebuilding its technical and commercial standing. The Seamaster Professional series became the face of that revival, uniting practical design with accessible luxury. The 2551.80’s success helped pave the way for the later co-axial movements that would come to define modern Omega.

Its successor, the 2222.80, introduced the calibre 2500 with the co-axial escapement and minor design updates. While the new movement represented progress, it also added thickness to the case. Many enthusiasts therefore prefer the original 2551.80 for its thinner profile and traditional mechanical feel. It stands as the last of the classic ETA-based Seamaster automatics before the co-axial era reshaped the line.

Enduring Appeal

The 2551.80 captures the balance between technical credibility and everyday wearability that defined Omega in the 1990s. Its design has aged gracefully: the blue wave dial remains striking yet understated, the aluminium bezel develops character through gentle fading, and the proportions suit almost any wrist. Even decades later, it feels relevant because it was designed with genuine purpose rather than trend.

On the wrist, it delivers everything that made the Seamaster 300M a success—robust construction, dependable accuracy, and a design language that still anchors Omega’s modern divers. It’s a reminder of an era when the brand focused on engineering excellence rather than excess. The 2551.80 endures not just as a collectible but as a practical, handsome mechanical watch that continues to do exactly what it was designed for: tell time reliably, above or below the surface.

Final Thoughts

The Omega Seamaster 300 Automatic 2551.80 remains one of the most balanced and thoughtfully executed divers of its time. With its 36.25 mm case, chronometer-certified calibre 1120 and 300-metre depth rating, it encapsulates everything Omega set out to achieve with the 1990s Seamaster line—precision, durability, and refinement. It represents the moment Omega reasserted itself as a leading watchmaker, combining modern manufacturing with timeless design.

Compact, capable, and instantly recognisable, the 2551.80 proves that good design and solid engineering never go out of style.

• Case in great vintage condition, light hairlines visible around the case.
• Bracelet also remains in great vintage condition with some wear visible around the clasp and links.

Dial & hands very good.