Introduction

The Audemars Piguet Royal Oak Double Balance Wheel Openworked (ref. 15407ST.OO.1220ST.02) isn't just a watch—it's a statement of intent. The 15407ST is the next-level flex: a skeletonized masterpiece that flaunts AP's technical prowess while retaining the iconic octagonal bezel that started the luxury sports watch revolution in 1972.

In the current market, this reference has become a barometer of hype. While the standard 15400 and 15500 have seen their secondary prices cool from peak madness, the Double Balance Wheel Openworked remains stubbornly above retail—a testament to its limited production and the fact that it's simply one of the most visually arresting Royal Oaks ever made. If you're considering a purchase, you're not just buying a watch; you're buying a position in a very exclusive club.

Manufacture History

Founded in 1875 in Le Brassus, Audemars Piguet has always been a family-owned powerhouse of haute horlogerie. The Royal Oak, launched in 1972, was the first luxury steel sports watch, designed by Gérald Genta. Its hexagonal bezel and integrated bracelet were a radical departure from the dress watches of the era, and it quickly became a symbol of rebellious luxury. The Double Balance Wheel Openworked continues this legacy of innovation, introducing a novel escapement architecture while celebrating the brand's tradition of skeletonization.

Movement

At the heart of the 15407ST beats the Cal. 3132, an automatic movement that features a double balance wheel system. Two balance wheels and two balance springs oscillate in unison, improving stability and precision by compensating for positional errors. The movement is meticulously finished with anglage, perlage, and Geneva stripes, visible through both the openworked dial and the sapphire caseback. The 45-hour power reserve and 21,600 vph frequency are standard, but the real star is the visual spectacle of the twin balances dancing in sync.

Specifications

  • Case Diameter: 41mm
  • Case Thickness: 9.8mm
  • Case Material: Stainless steel
  • Crystal: Sapphire (front and back)
  • Water Resistance: 50m
  • Bracelet: Stainless steel integrated bracelet with folding clasp
  • Movement: Cal. 3132, automatic, 38 jewels, 45h power reserve

Wrist Feel

On the wrist, the 15407ST wears like a tailored suit—slim, balanced, and surprisingly comfortable. The 41mm case hugs the wrist without overhang, and the integrated bracelet drapes elegantly, distributing weight evenly. The openworked dial catches light from every angle, making it a constant conversation starter. Despite the skeletonization, the watch remains robust; you'll forget it's on until you catch a glimpse of the mechanical ballet.

Accuracy

In real-world use, the double balance wheel system delivers excellent chronometric performance. Expect +2 to +5 seconds per day, well within COSC standards even without certification. The twin balance wheels reduce positional errors, so the watch remains consistent whether you're at your desk or at a yacht party. Over a week, you'll likely lose less than 20 seconds.

Occasions

This watch is versatile enough for formal wear, daily use, and even sporty events (though you'll want to avoid swimming). It's a dress watch that can be worn with a tuxedo or a polo shirt. The openworked dial is a talking point, so be prepared for questions.

Wrist Presence

5/5 - The openworked dial is a spectacle. The combination of the steel case, the intricate movement, and the iconic octagonal bezel ensures this watch dominates any room. It's not subtle—it's a deliberate, loud statement of horological appreciation and financial firepower.

Reference Variants

The 15407ST is the stainless steel version, but AP also offers it in rose gold (15407OR), white gold (15407BC), and titanium (15407SK). Each variant carries the same movement and openworked design, but the case material changes the character. The rose gold is warmer and more opulent; the white gold is stealthy; the titanium is lighter and more modern.

Family References

The 15407ST belongs to the Royal Oak family, which includes the classic 15400ST, the newer 15500ST, and the ultra-thin Jumbo 15202ST (now 16202ST). These are the non-skeletonized versions, each with their own cult following. The Double Balance Wheel Openworked sits above them in terms of complexity and visual impact.

Similar Watches

For collectors seeking alternatives, the Patek Philippe Nautilus 5711/1A is the obvious rival, though it doesn't offer skeletonization. The Vacheron Constantin Overseas Skeleton is a more direct competitor with a similar openworked aesthetic. Richard Mille's RM 030 is a more avant-garde option, but at a significantly higher price point.

Homages

Budget-conscious buyers might look at skeletonized watches from Invicta, Sevenfriday, or Bomberg, but these lack the heritage, finishing, and investment potential of the AP. They're not true homages to the Royal Oak specifically, but they offer a glimpse of skeletonization for a fraction of the cost.

Investment Value

With an MSRP of $80,000 and a current retail price of $82,000, the 15407ST trades at a premium in the secondary market, ranging from $75,000 to $95,000 depending on condition and box/papers. The trend is appreciating, driven by limited production and high demand. For the investor, this is a hold—it's a modern classic that will likely continue to gain value. Auction results have been strong, with pieces consistently exceeding retail.

Service Interval

AP recommends servicing every 5 years, with an approximate cost of $1,500. The service must be done by an authorized AP service center to maintain warranty and authenticity. Expect a turnaround of 3-6 months.

Price Range

In the current market, you'll find pre-owned examples between $75,000 and $95,000. This is a flex that holds value—an investment piece that also happens to be a masterpiece.

Pros and Cons

  • Pros: Iconic design with openworked movement; double balance wheel improves accuracy; strong secondary market value; superb finishing and craftsmanship.
  • Cons: High price point; not for subtle tastes—attracts attention; service costs are steep; limited water resistance for a sports watch.

Final Verdict

The 15407ST is the ultimate Royal Oak for the collector who wants to showcase AP's technical prowess without sacrificing the brand's iconic design. It's a watch that commands respect, holds its value, and will continue to be a grail for years to come. If you have the means, this is a no-brainer addition to any serious collection.