Audemars Piguet Royal Oak “Jumbo” Extra‑Thin Openworked – 18ct Yellow Gold (Ref. 16204BA.OO.1240BA.01) – Calibre 7121 – 247 Hand-Polished V‑Angles. 18ct Gold. Pure AP Mastery.
At Calibre24, we are proud to present one of the most technically impressive and artistically significant Royal Oak models ever created. The Audemars Piguet Royal Oak Jumbo Extra‑Thin Openworked 16204BA.OO.1240BA.01 in 18ct yellow gold represents the pinnacle of AP’s craftsmanship—an extraordinary fusion of mechanical mastery, architectural beauty, and ultra‑thin engineering.
This example is a 2023 full set, fully stickered with protective film, in Mint condition, and includes the balance of AP warranty until Q4 2028.
A Landmark in Royal Oak History
The Audemars Piguet Royal Oak “Jumbo” Extra‑Thin Openworked 16204BA.OO.1240BA.01 is the first-ever openworked Jumbo crafted in yellow gold, making it a milestone reference for collectors. It debuts an entirely new skeletonized mechanism, measuring an astonishing 2.7mm in thickness, housed within an 8.1mm ultra‑thin case—a testament to AP’s relentless pursuit of horological excellence.
Technical & Artistic Highlights
Calibre 7121 – AP’s First In‑House ‘Extra‑Thin’ Jumbo Movement
- The 16204BA introduces the first in‑house extra‑thin movement ever used in a Jumbo.
- Calibre 7121 replaces the historic 2121, offering improved efficiency, stability, and finishing.
- Despite its modern upgrades, it remains remarkably slim, incredibly beautiful, enabling the iconic Jumbo profile.
247 Hand‑Polished V‑Angles
- The openworked bridges and plates feature 247 hand‑finished V‑angles, each requiring exceptional skill.
- These sharp interior angles cannot be replicated by machine—only by the hands of AP’s master artisans.
- The result is a breathtaking interplay of light, depth, and geometry.
Ultra‑Thin Architecture
- Case thickness: 8.1mm
- Skeletonized movement thickness: 2.7mm
- The watch maintains the legendary proportions of the Royal Oak Jumbo while revealing its mechanical soul.
18ct Yellow Gold Construction
- Case and bracelet crafted entirely in 18ct yellow gold
- Contrasting satin brushing and mirror polishing highlight the Royal Oak’s iconic geometry
- Openworked dial reveals the movement’s architecture in full depth and detail
Condition & Inclusions
- Condition: Mint, fully stickered with protective film
- Year: 2023
- Warranty: AP international warranty valid until Q4 2028
- Set: Full set with box and papers
The Audemars Piguet Royal Oak “Jumbo” Extra‑Thin Openworked 16204BA is not just a watch—it is a masterpiece of modern haute horlogerie. As the first openworked Jumbo in yellow gold, powered by AP’s first in‑house extra‑thin movement and finished with nearly 250 hand‑polished V‑angles, it stands among the most collectible Royal Oaks ever produced.
For the discerning collector, this is an opportunity to secure a future icon, preserved in mint, fully protected condition with long factory warranty.
Please note that we don’t use catalog photos rather all the photos on this listing are taken from the actual Audemars Piguet Royal Oak “Jumbo” Extra‑Thin Openworked timepiece for sale and are our intellectual property across all our platforms. The photos showcase the very timepiece that is available for sale i.e. what you see is exactly what you will receive, shall you wish to purchase this timepiece.
The serial number and the card details are redacted in all the photos for privacy and security reasons.
Please further note that since we use macro and high-resolution equipment for the photos, there may be fingerprints or some dust/debris that may show in the photos.
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