Omega Seamaster Diver 300M Master Co-Axial 42 Stainless Steel / Blue / Bracelet 210.30.42.20.03.001

The fourth generation of the Omega Seamaster 300M was introduced at BaselWorld 2018, marking the return of the wave-dial and the introduction of the Co-Axial Master Chronometer caliber 8800. It is available in a number of variations; reference 210.30.42.20.03.001 has a blue dial and matching ceramic bezel insert; it is fitted with a stainless steel bracelet.

Watch our tour video about the OMEGA SEAMASTER DIVER 300M BLUE 210.30.42.20.03.001

If you’ve spent any time exploring dive watches, the Omega Seamaster 300M is likely already on your radar. Among the various models in the collection, the reference 210.30.42.20.03.001 stands out for its vibrant blue wave dial, everyday versatility, and connection to Omega’s long-standing dive heritage.

This particular Seamaster bridges tradition and innovation – pairing a laser-engraved ceramic dial with a reliable METAS-certified automatic movement. It’s sporty, stylish, and purpose-built, making it a favorite among collectors, enthusiasts, and even James Bond himself.

But what exactly makes this version special?

Let’s walk through the story behind it, its specs, and how it feels on the wrist.

The Seamaster Legacy: Where It All Began

The Omega Seamaster first launched in 1948, designed as a robust everyday watch with water-resistant capabilities. While it wasn’t originally positioned as a dive watch, that changed in the 1950s, when Omega leaned heavily into underwater exploration. By the time the Seamaster 300 debuted in 1957, Omega had created a serious contender in the tool watch category.

Fast-forward to 1993, and the Seamaster Diver 300M made its first appearance with a wave dial, helium escape valve, and quartz or automatic options. That release introduced the modern DNA of the Seamaster series as we know it today – and it’s that same lineage that this 2018 update pays tribute to.

The current reference 210.30.42.20.03.001 improves on the original blueprint while staying true to its roots.

Case & Bracelet: Built for Land, Sea, and Everything in Between 

This watch measures 42mm in diameter, with a stainless steel case that gives off a sturdy but not bulky impression. The case features a mix of brushed and high-polished surfaces, helping the watch catch light without feeling flashy.

At 13.5mm thick, it wears with a solid wrist presence but doesn’t overwhelm. The lug-to-lug length is about 50mm, making it wearable even for mid-sized wrists, especially with the downward curve of the lugs.

On the right, you’ll find the screw-down crown, which is protected by polished guards. At 10 o’clock, the familiar helium escape valve is still there – a signature of the Diver 300M line.

The watch is paired with a stainless steel bracelet, featuring brushed outer links and polished inner accents. It feels fluid on the wrist and is secured by a folding clasp with a diver extension, so you can make quick adjustments whether you’re wearing it over a wetsuit or not.

If you prefer a sportier or more casual look, this model is also compatible with Omega’s rubber strap options.

Dial Design: The Return of the Wave 

The blue ceramic dial is the first thing that grabs your attention – and for good reason. It’s not just blue; it’s laser-engraved with a wave pattern that reflects light from different angles, giving it depth and movement. Unlike earlier models where the wave design was stamped, this version’s precision makes the dial feel more dynamic.

The hour markers are raised and filled with white Super-LumiNova, glowing blue in low light. The skeletonized sword hands also have luminous material, the hour hand glowing blue and the minute hand glowing green for easy readability in the dark.

You’ll also find a framed date window at 6 o’clock, which is a big shift from previous models that had it at 3. This creates a cleaner, more symmetrical dial layout that many collectors appreciate.

The ceramic bezel is filled with white enamel and rotates unidirectionally – perfect for tracking dive times or just your lunch break.

Movement & Functions: Master Chronometer Certified 

Inside beats the Omega Master Chronometer Caliber 8800, a self-winding movement that is METAS-certified for accuracy, anti-magnetism, and performance. It’s visible through the sapphire exhibition caseback, where you can see the rotor and Geneva waves in arabesque.

Key specs of the Caliber 8800:

• 55-hour power reserve
• 3.5 Hz frequency (25,200 vibrations per hour)
• Co-Axial escapement for long-term stability
• Anti-magnetic up to 15,000 gauss

It also has a free-sprung balance with silicon hairspring, which improves reliability across different positions and temperatures.

In terms of functions, you’re working with:

• Hours, minutes, central seconds
• Quick-set date at 6 o’clock
• Hacking seconds for precise time-setting

In addition to the internal functions, this watch features components essential for diving:

Unidirectional Rotating Bezel:

Made of blue ceramic with white enamel markings, the bezel rotates counter-clockwise only – an important safety feature for divers. It lets you track elapsed time underwater without the risk of accidentally extending it. Even outside of diving, it’s a practical tool for timing everyday events.

Helium Escape Valve:

Positioned at 10 o’clock, the manual helium escape valve is designed for saturation divers who spend extended time in pressurized environments. It allows helium particles that have entered the watch during deep dives to safely escape during decompression, protecting the integrity of the case.

Water Resistance:

The Seamaster Diver 300M lives up to its name with a water resistance rating of 300 meters (1000 feet). This makes it suitable for recreational scuba diving, surface swimming, and everyday wear around water. The screw-down crown, sealed caseback, and overall build help keep water from entering the case.

Together, these features ensure the watch is not only accurate but also fully capable of handling professional dive conditions.

On-Wrist Feel: Balanced, Sporty, Comfortable 

Despite its tool-watch roots, this Seamaster wears comfortably for a variety of wrist sizes. The 42mm case sounds large on paper, but the curved lugs and ergonomic caseback keep it snug. 

Whether you’re wearing it with a t-shirt, a wetsuit, or even under a cuff, it settles nicely.

The bracelet doesn’t feel stiff or heavy and includes a folding clasp with a diver’s extension that allows for micro-adjustments. This feature is especially useful if your wrist size changes throughout the day or seasons.

It’s not a light watch, but it doesn’t drag your wrist down either. The case sits securely, and the ceramic bezel adds a slight sense of luxury while still being completely functional.

Seamaster 300M Blue Wave Dial Specs at a Glance:

Final Thoughts: Is This the Seamaster for You? 

The Omega Seamaster 300M 210.30.42.20.03.001 delivers a blend of heritage and tech without asking you to pick a side. The wave dial is a direct callback to earlier models, while the ceramic materials, anti-magnetic movement, and date placement reflect Omega’s push toward modern utility.

It’s a great choice for someone who wants a dive watch that works both above and below the surface. Whether you’re taking it into the ocean or just into a work meeting, it performs and looks the part.

And if you’re looking for that one steel sports model that doesn’t copy anything else – this is a strong candidate.