Case #767 — Omega Planet Ocean 43.5 Blue Ref. 215.30.44.21.03.001

Case #767 — Omega Seamaster Planet Ocean 600M "Blue Ceramic"

Ref. 215.30.44.21.03.001

Status: Available

Condition: Very Good Pre-Owned

Scope: Box, Papers, and Cards

Year: 2020

🔎 Case Notes

Some dive watches whisper. This one states its case plainly. The Planet Ocean 600M in 43.5 mm steel is Omega's full-dress professional diver — broad-shouldered, legible from across a room, and engineered well past the point where most owners will ever test it. The blue ceramic dial, Liquidmetal™-filled ceramic bezel, steel bracelet and Calibre 8900 combine with a screw-in crown and helium escape valve to support 600 metres of water resistance.

The blue here is the point. Omega produces these dials in high-gloss zirconium oxide ceramic rather than lacquered brass, which gives the surface a depth and a glassiness that shifts constantly as the wrist moves — it reads near-navy in shade and vivid under direct light. The matching ceramic bezel carries its diving scale in OMEGA Liquidmetal™, a bonded alloy rather than paint, so the numerals sit flush with the ceramic surface.

This example is graded Very Good Pre-Owned. It presents as a watch that has been worn and enjoyed rather than stored: very minor visible wear is present on the high-polished areas and on the clasp, which is precisely where a steel sports watch collects its history first. The ceramic dial and bezel are, by their nature, unaffected by the kind of light contact that marks polished steel.

It arrives as Box, Papers, and Cards, and is currently sized to fit an approximately 7¾-inch wrist.

🕰️ The Evidence

• Reference: 215.30.44.21.03.001
• Model / Collection: Seamaster Planet Ocean 600M Co-Axial Master Chronometer 43.5 mm
• Year: 2020
• Case: Stainless steel, brushed and polished
• Case Diameter: 43.5 mm
• Thickness: 16.09 mm
• Lug-to-Lug: 49.00 mm
• Lug Width: 21 mm
• Dial: Blue ceramic, dot and stick indices with luminous filling, large Arabic numerals and a date window at 3 o'clock
• Crystal: Domed scratch-resistant sapphire with anti-reflective treatment on both sides
• Bezel: Blue ceramic unidirectional bezel with OMEGA Liquidmetal™ diving scale
• Crown: Screw-in crown; helium escape valve at 10 o'clock
• Caseback: Alveol screw-in caseback, transparent, displaying the movement
• Movement: OMEGA Calibre 8900
• Movement Type: Automatic, self-winding with Co-Axial escapement
• Certification: Master Chronometer, certified to the eight tests set by METAS (Swiss Federal Institute of Metrology); resistant to magnetic fields reaching 15,000 gauss, free-sprung balance with silicon balance spring
• Power Reserve: Approximately 60 hours, via twin barrels mounted in series
• Functions: Hours, minutes, seconds, date, independent hour hand, unidirectional timing bezel
• Water Resistance: 600 metres / 2000 feet / 60 bar
• Bracelet: Stainless steel bracelet with patented extendable foldover clasp
• Clasp: Deployant / folding clasp with push-button release
• Bracelet Fit: Approximately 7¾-inch wrist
• Condition: Very Good Pre-Owned — very minor visible wear to high-polished areas and clasp
• Included: Box, Papers, and Cards

🌟 Collector Provenance

Omega launched the Planet Ocean line in 2005, positioning it above the Diver 300M as the collection's uncompromised professional tool: deeper rated, larger cased, and visually descended from the 1950s and 1960s Seamaster 300 rather than from the Bond-era Seamaster. Where the Diver 300M has always carried a certain dress-diver polish, the Planet Ocean was designed to look like equipment.

This 43.5 mm reference belongs to the generation that moved the collection onto Master Chronometer architecture. It is the mid-size of the current family, sitting between the 39.5 mm and the 45.5 mm cases, and for most buyers it is the version that defines the model — large enough to deliver the broad-arrow-hand legibility the line is known for, without the wrist presence of the largest case.

What distinguishes this particular configuration within the family is its full-ceramic treatment of both dial and bezel in matching blue. Collectors tend to separate Planet Oceans into the earlier aluminium-bezel, lacquer-dial era and the later ceramic era; this reference sits firmly in the latter, and the coherence of ceramic-on-ceramic in a single colourway is the reason it remains among the most recognizable steel divers Omega currently builds.

🌟 Technical Provenance

The Co-Axial escapement is the technical argument at the centre of modern Omega, and Calibre 8900 is one of its most resolved expressions. It runs at 25,200 vph, carries 39 jewels, and draws approximately 60 hours of reserve from twin barrels mounted in series — with a Si14 silicon balance spring improving resistance to shock and magnetism.

Master Chronometer status is the more consequential detail. Certification requires passing eight tests administered by METAS, the Swiss Federal Institute of Metrology, covering precision, performance and magnetic resistance — testing conducted on the cased watch rather than the bare movement alone, which is a meaningfully different standard from chronometer certification of a movement in isolation. The 15,000-gauss magnetic resistance figure is a direct consequence of that silicon-and-non-ferrous construction.

The case engineering follows the same logic. A screw-in crown that locks into the case tube, an alveol screw-in caseback, and a helium escape valve support the 600-metre rating — the helium valve being saturation-diving hardware that most owners will never use and most enthusiasts quietly enjoy owning anyway.

🧾 From the Case File

At 43.5 mm wide, 49 mm lug-to-lug and roughly 16.1 mm thick, this is an honest sports watch and should be understood as such. The 49 mm lug span is the number that matters most: it keeps the case within the footprint of a 7-inch-plus wrist despite the diameter, and the downturned lugs help the bracelet break early.

The bracelet itself is a genuine practical advantage. Omega fits a satin-finished steel bracelet with a patented folding push-button clasp offering both a diving extension and comfort adjustment settings — meaning on-the-fly micro-adjustment without tools, which is the single feature most likely to change how a heavier watch feels across a day. It is currently sized for an approximately 7¾-inch wrist.

Day to day, the ceramic components earn their keep. A ceramic bezel insert will not fade or scuff the way anodised aluminium does, and a ceramic dial is immune to the UV drift that affects painted dials over decades. Combined with double-sided anti-reflective treatment on the domed sapphire, legibility is excellent in the exact conditions — bright sun, water, movement — where dive watches are usually hardest to read.

Buying at Very Good Pre-Owned is a deliberate trade. The very minor wear on the polished surfaces and clasp is visible on close inspection and is disclosed as such; in exchange, the buyer takes on a full-specification Master Chronometer diver with its box, papers and cards intact, and is spared the anxiety of the first bracelet scuff.

Buy with Confidence

BST guarantees the authenticity of every watch we sell and provides a 30-day mechanical performance guarantee under normal use.

Accuracy may vary with age and service history, and water resistance is not guaranteed unless specifically stated and pressure-tested.

🗝️ BST Verdict

A well-worn but well-kept example of Omega's most assertive steel diver, in the ceramic-on-ceramic blue configuration that best represents the current Planet Ocean. The dial and bezel are the reason to want it; the Calibre 8900 and METAS certification are the reasons to trust it.

Complete with Box, Papers, and Cards, sized to an approximately 7¾-inch wrist, and honestly graded. A watch for someone who intends to wear it rather than preserve it.

👉 Every case deserves a closer look.