The Royal Oak Offshore Diver is the time-only, professional dive version of the Royal Oak Offshore line. It pairs the augmented Offshore case with a 300 meter water resistance rating and an internal rotating dive bezel, giving the collection a dedicated tool-diver alongside its chronograph models. Reference 15720ST.OO.A027CA.01 is the blue dial configuration in stainless steel.
The Offshore Diver traces back to the Offshore Scuba shown in 2005 and became a permanent, chronograph-free model named Diver in 2010 (reference 15703ST). A second generation, reference 15710ST, followed in 2015 with a sapphire caseback and minor updates.
This reference belongs to the third generation, introduced in 2021, which retained the external case profile but added the in-house selfwinding Calibre 4308, a sapphire display caseback, black ceramic screw-locked crowns in place of the earlier rubber-clad crowns, a redesigned dial carrying the simplified AP monogram, and a patented quick-release interchangeable strap system. It launched as one of three steel color options released together: khaki green (15720ST.OO.A052CA.01), gray (15720ST.OO.A009CA.01), and blue (15720ST.OO.A027CA.01).
The dial is blue with the “Méga Tapisserie” pattern, a large-format version of the quilted guilloché used across the Royal Oak family. The hour markers are applied white gold with a luminescent coating, and the hands are white gold Royal Oak hands, also luminescent.
A black rotating inner bezel with a white minute scale running from 60 to 15 sits at the dial’s outer edge and is driven by the crown at 10 o’clock. A magnified date window is positioned at 3 o’clock.
Printed dial text is the AP monogram beneath 12 o’clock, “300m/1000ft” and “AUTOMATIC” to the right of center, and “SWISS MADE” at 6 o’clock. The monogram replaces the full “Audemars Piguet” wordmark carried on the earlier 15710ST generation.
The case is stainless steel in the octagonal Royal Oak Offshore form, brushed across the main surfaces with polished beveled edges. The published diameter is 42 mm, with case height listed at 14.1 mm at launch (some later sources cite 14.2 mm). The crystal is glareproofed sapphire.
The caseback is a screwed sapphire display back, glareproofed, exposing the movement. Two black ceramic screw-locked crowns are fitted: one for winding and time and date setting, and one at 10 o’clock for operating the internal bezel. Water resistance is 300 meters.
The outer octagonal bezel is fixed stainless steel, secured by eight hexagonal screws in the Royal Oak manner. The dive timing function is handled by the unidirectional rotating inner bezel under the crystal, read against the white 60 to 15 minute scale and advanced by the 10 o’clock crown.
This reference uses the third-generation interchangeable rubber strap system rather than a bracelet. The quick-release mechanism is integrated into the case studs and the buckle, allowing the strap to be changed by hand without a tool.
The strap is secured by a stainless steel pin buckle. The example configuration ships fitted with a blue rubber strap and includes an additional black rubber strap.
Because the reference is strap-only with a proprietary attachment system, it does not use a conventional lug-width fitting; straps are matched to the interchangeable studs.
The movement is the Audemars Piguet Calibre 4308, an in-house selfwinding caliber based on the movement architecture introduced with the Code 11.59 by Audemars Piguet collection in 2019. It measures 32 mm in diameter and 5.2 mm in height and is built from 234 parts.
It runs at 28,800 vibrations per hour (4 Hz), holds 32 jewels, and provides a 60 hour power reserve. Functions are hours, minutes, central seconds, and date.
Winding is by a central rotor in blackened 22 carat pink gold. Visible finishing through the sapphire caseback includes Côtes de Genève, circular graining, and beveled edges.
Operation is straightforward: the movement crown winds and sets the time and date, while the 10 o’clock crown rotates the internal dive bezel to mark elapsed time.
Case, outer bezel, buckle, and crown stems: stainless steel. The two crowns are black ceramic, which resists scratching and corrosion at the most handled points of the case.
The crystal and the caseback window are sapphire, both with anti-reflective treatment. The hour markers and hands are white gold with a luminescent coating. The strap is rubber, supplied in two colors for this reference.
The movement’s oscillating weight is 22 carat pink gold, blackened. Overall the watch combines a steel and rubber tool-diver build with white gold dial furniture and ceramic crowns at the wear points.
A full set for this reference’s era typically includes:
The additional rubber strap is a reference-specific inclusion. A full set is incomplete without the second strap, since the interchangeable system was sold as a two-strap package.
Older version (Generation 1, approximately 2021 to present)
Newer version
Documented sets from 2021 through 2025 carry the same green presentation format throughout the reference’s production run to date. Dealer-stock differences are not treated as a separate generation. A service-replacement box on an example returned to Audemars Piguet would be the standard current box.
Audemars Piguet supplies its International Sales Warranty against manufacturing defects for two years from the date of initial purchase from an Audemars Piguet boutique, AP House, or authorized dealer. The warranty can be extended to five years free of charge by registering the watch online through an AP Account.
For this reference’s 2021 onward production, documentation at the point of sale is a dark Audemars Piguet plastic warranty card carrying the case and serial number, the warranty number, and the collection and reference fields, with QR-based online registration. Coverage is international.
Older version (Generation 1, approximately 2021 to present)
Newer version
Audemars Piguet revised its warranty-card design around early 2021, close to this reference’s launch. No example of 15720ST.OO.A027CA.01 has been documented with the preceding card format, so an older-card example is unconfirmed rather than a separate documented generation. The base warranty runs two years from the original purchase date and, where registered online, five years, so coverage status depends on that example’s individual purchase date. The completed, dated card is the primary purchase documentation for a full set.
At a published 42 mm diameter and roughly 14.1 mm in height, this is a substantial watch that wears with the presence expected of the Offshore case rather than as a slim dress diver. The octagonal case and thick bezel add visual and physical size beyond the nominal diameter.
The rubber strap and integrated stud fitting keep the watch close to the wrist, and the quick-release system allows a change between the fitted and additional straps without tools. The case height suits medium to larger wrists and reads as a sports and tool watch rather than an under-cuff piece.
It fits a wearer who wants a professional-rated dive watch with the Royal Oak Offshore design language, suited to active and casual use given the 300 meter rating and rubber strap.
This reference is a single configuration: a 42 mm stainless steel case, blue “Méga Tapisserie” dial with white gold applied markers and Royal Oak hands, black rotating inner bezel, black ceramic crowns, and the Calibre 4308, supplied on an interchangeable rubber strap with a stainless steel pin buckle and a second rubber strap included.
It sits within a three-color steel release under the 15720ST generation.
These are distinct references and their specifications do not carry across to 15720ST.OO.A027CA.01.
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