The Manta S6000 collection — by Casio’s premium sub-brand Oceanus — represents the Japanese watchmaker’s highest echelon.

The Manta OCWS6000SW2A Limited Edition measures a sleek 42.5 mm x 9.2 officially, however, Oceanus, included the crown guards in the official diameter specification whereas we typically don’t include crown guards when measuring the diameter of a watch case, meaning this watch realistically looks and wears more like a 41 mm watch. Moreover, with a relatively short lug-to-lug of 47.1 mm, it should fit many wrist sizes quite well.

2023 Oceanus Manta OCWS6000SW2A Limited Edition flat lay

Being made of lightweight titanium and having such svelte dimensions translates to a low total weight of just 88 grams, which is especially nice considering this has a fully metallic integrated bracelet. The result is a comfortable on-wrist experience with the feel of a dress watch — that effortlessly slides right under the cuff of a dress shirt — yet unlike your typical dress watch it’s not fragile. And like a sports watch, it’s equally attractive with a short-sleeved shirt.

2023 Oceanus Manta OCWS6000SW2A Limited Edition wristshots

While MR-G timepieces represent the top-of-the-line from G-Shock — Oceanus is the elevated sub-brand of Casio (all owned by Casio). Notably, Oceanus has always been a more prestigious line within the overall group, mostly sold in Japan, however, in the past few years, Oceanus has moved into the US and has been elevated further upscale, and that’s more apparent within the Manta S6000 collection than ever before.

Oceanus Manta S6000 Limited Edition monoblock sapphire bezel

Oceanus implemented a distinctive blue frameless, one-piece sapphire crystal bezel, achieved using a special spiral-cutting production technique, and by applying a blue graduated ion-plating/vapor deposition treatment to the underside of the bezel which creates a range of blue hues that matches the blue gradient dial. Made from a synthetic sapphire crystal material, with a polygonal shape on the sides, and a wave pattern on the top, there are cuts on 48 sides in total, with each facet perfectly polished to a jewel finish — resulting in a gorgeous sparkle effect created by every ray of light that hits the surfaces, on both the horizontal and vertical axes of the bezel.

2023 Oceanus Manta OCWS6000SW2A Limited Edition closeup

Both the (pictured) limited edition OCWS60002A and the regular production OCW-S60001A models, the latter of which has a flat surface on the top of its bezel, remind me of the understated bling of a standard Royal Oak, which utilizes multiple sharp angles and facets coupled with intricate polishing techniques to reflect light — without putting your wrist on blast like a diamond-set bezel does — elegantly.

2023 Oceanus Manta OCWS6000SW2A Limited Edition

As you can see in the profile view image above, the sapphire crystal bezel is quite thick (approximately 3 mm thick). Separately, you can see there’s an uneven space between the top of the rectangle push piece and the frame around it. At first, I thought this was a defect, but it actually appears to be how the pushers were designed because the other pusher is a mirror image of this.

2023 Oceanus Manta OCWS6000SW2A Limited Edition closeup

The blue bezel, like the clear synthetic sapphire crystal that protects the dial, does have the potential to shatter, however, it would require an incredible amount of force being that sapphire has a 9 on the Mohs hardness scale (second only to a diamond, which is a 10). This level of hardness makes scratching of the sapphire glass virtually impossible. In comparison to a steel bezel, which can be gouged and dinged, or a diamond set bezel, where the diamonds can fall out of the setting, this configuration should be more durable in most circumstances.

2023 Oceanus Manta OCWS6000SW2A Limited Edition flat lay angled

Similar to a premium G-Shock — though not as heavily shock and impact-resistant — the Manta S6000 is powered by an advanced Japanese quartz movement that’s equipped with solar-powered charging with an approximate battery operating time of 5 months on rechargeable battery (operation period with normal use without exposure to light after charge) 18 months on rechargeable battery (operation period when stored in total darkness with the power save function on after full charge), multi-band 6 atomic time calibration (as a backup to Bluetooth), and Bluetooth time syncing (requires Casio Watches app connection for each calibration). Like with other premium models across Casio’s range, there’s a power-saving feature where the hands stop to save power when the watch is left in the dark. If paired with your phone, there’s an automatic time correction (4 times a day). And if that’s not possible, atomic timekeeping automatically kicks in and attempts to calibrate 5-6 times a day (depending on which radio antenna is closest to your location). Even without successful Bluetooth or atomic calibration, the watch keeps time with an accuracy is -15/+15  seconds per month.

2023 Oceanus Manta OCWS6000SW2A Limited Edition

The dial is coated with a gradation of vapor deposition that changes from light blue to blue, which matches the bezel. The monochromatic blue vapor deposition that decorates the dial has a sunburst pattern at certain angles and more of a mirrored gradated look at other angles. Oceanus really elevated the look of the dial, especially considering that it has this level of detail, despite needing to pass light through it to charge the watch’s battery via the Tough Solar technology (which is seen on G-Shock and other Casio products).

2023 Oceanus Manta OCWS6000SW2A Limited Edition lumeshot

Prominent, applied, faceted indices mark the hours of the dial for enhanced legibility. Once it becomes dark, legibility is maintained thanks to a white lume that emits a blue glow on the hour hand, minute hand, and eleven indices have a white lume that emits a blue glow (there’s no hour index where the date aperture is located). There’s not as much luminous material as a dive watch but the legibitliy is relatively high thanks the the long form factor of the hands and markers.

2023 Oceanus Manta OCWS6000SW2A Limited Edition crownshot

Oceanus powers the limited edition OCWS60002A shown, and regular production OCWS60001A with the exact same Japanese Quartz Module 5665, that features solar/radio-controlled/Bluetooth. The cases are bracelets for each reference are nearly the same as well, though the standard production model is actually slightly thinner at 8.7 mm versus 9.2 mm on the limited edition, and this is simply due to the spiral cut top of the bezel being a half a millimeter taller. To achieve such thinness, Oceanus miniaturized the components for this movement module, used a special high-density substrate mounting on one side, and implemented a flat sapphire crystal to protect the dial.

2023 Oceanus Manta OCWS6000SW2A Limited Edition wristshot

Made of titanium with a hardened carbide treatment to resist wear and coloration, the exterior of the watch case and bracelet is more durable than a raw titanium finish could provide, though don’t expect the carbide treatment to fully prevent scratches the way ion-plating treatments tend to do. The Manta has a mixture of satin-brushed finishes and the mirror surface portion is “polished to a beautiful surface without distortion by rough polishing. It is carefully polished by skilled craftsmen,” according to Oceanus.

2023 Oceanus Manta OCWS6000SW2A Limited Edition clasp

The small 5.1 mm diameter crown is non-locking and has been treated with pink gold IP plating, which is echoed on the large faceted hour marker at 12, on the center seconds hand, and on the frame around the date aperture at 3 o’clock. The caseback is titanium and is thin and flat and does not have any decorative markings, just technical information. The watch is not designed for diving but does have a respectable depth rating of 100 meters which is sufficient for swimming and other water activities.


With a $2,400 price tag —  this is one of the most expensive Oceanus timepieces ever created — it’s up there with some of the priciest quartz timepieces on the market. However, there’s also a standard Manta S6000 model for $1,800 that arguably has equal or better features, with the exception of having a more standard version of the sapphire bezel, sans the spiral cut wave pattern. If you prefer black dials, don’t care for the pink gold treatment, and don’t mind saving $600, the standard Manta S6000 is absolutely the way to go.

The none limited version of the Manta S6000 is in many ways the better choice here, coming in at $1800 ($600 less), with the exact same solar-powered/radio-controlled/Bluetooth quartz movement Module 5665, nearly the same titanium case (except it’s even thinner at 8.7 mm), all the same functions (and instead of a blue dial, it comes with a black dial with no gold accents. The five main differences are the dial color, the thickness, the price, the non-limited designation, and a blue sapphire bezel without the 48-sided spiral cuts. Of those, the only thing I’d personally like to see on the standard model is the spiral-cut bezel. However, the regular monoblock sapphire bezel certainly looks fantastic as well, albeit without as much light refraction from the different angles.

Functionally, the Manta S6000 Limited Edition and regular production models are the same, offering regular analog timekeeping via 3 hands (hours, minute hand that moves every 10 seconds, center seconds, 3 dials which offer dual time hours and minutes, 24-hour dual time dial, and the ability to switch the second time zone dial to a stopwatch (that can time up to 24-hour periods) via the app. They offer a date display at 3 o’clock, and a dedicated day indicator display in the lower right of the dial. Additional features include a world time second time zone display (with an am/pm indication), that shares the readout with the stopwatch, which can be toggled within the Casio Watches app.  There’s also a display of the solar power generation status, as well as a mobile phone finder feature that activates a sound on your phone by pressing a button on the watch.

Overall the watch functionality is advanced without having too much complexity within the app or on the dial. However, I do have to point out that when I switched to stopwatch mode from within the app (multiple times), once I tried to activate the stopwatch via the top pusher, instead of starting the chronograph function, it disabled the Casio Watches app Bluetooth connection every time. The watch sent to us on loan is explicitly marked with an “S” engraving on the caseback, meaning it’s a pre-production model, so this will presumably be rectified in a software update prior to shipping.

The lightweight titanium carbide-treated bracelet is fantastic and has been finished by Casio’s most skilled craftsman, and has the ability to add half links, however, there are no micro-adjustments and the bracelet links use a collar and pin system. I’d prefer to have micro-adjustments and screwed bracelet links.

Limited to just 350 pieces worldwide, the Manta S6000 Limited Edition very special timepiece that’s thin, and elegant, and has an attractive graduated dial and matching bezel that’s truly unique on the market.

Learn more at Oceanus.



Oceanus Manta S6000 Limited Edition

Reference: OCWS6000SW2A

Year: 2023

Total Weight: 88 grams stated

Case material: titanium (sapphire crystal bezel)

Case Diameter: 42.5 mm (41 mm excluding crown guards)

Case thickness: 9.2 mm

Lug-to-Lug: 47.1 mm

Lug Width: 20.5 mm (approximate)

Crown Diameter: 5.1 mm (non-locking)

Movement: Japanese Quartz Module 5665 (solar/radio-controlled/Bluetooth)

Depth Rating: 100 meters

Bracelet: Titanium deployant (no micro adjustments)

Posted by:Jason Pitsch

Jason is the founder of Professional Watches and specializes in writing, product photography, and digital marketing.