Audemars Piguet Royal Oak Jumbo Extra-Thin Openworked 50th Anniversary (Ref. 16204ST.OO.1240ST.01)
Table of Contents
Watch the full unboxing
This is the Audemars Piguet Royal Oak Jumbo Extra-Thin Openworked, reference 16204ST.OO.1240ST.01. It came to us unworn, and we filmed the whole unboxing. It is a stainless steel Jumbo with an openworked caliber 7124, released as part of the Royal Oak's 50th anniversary.
The Jumbo is the watch that started the Royal Oak in 1972. This openworked version keeps those proportions and opens the dial up to the movement underneath. It is one of the more impressive steel Royal Oaks we have handled, so here is a closer look at what stood out.
The steel Jumbo Extra-Thin Openworked, reference 16204ST.
A 50th Anniversary Royal Oak
The Royal Oak turned 50 in 2022, and Audemars Piguet marked the occasion across the collection. This reference shipped a little after that calendar year, and it carries the 50-year rotor that ties it to the anniversary. Turn it over and the sapphire caseback shows the openworked movement and a 22-carat gold rotor engraved for the anniversary. That marking is something only the owner sees, which is part of why we like it.
Through the sapphire caseback: the openworked caliber 7124 and the 50-year anniversary marking.
It comes in the full Audemars Piguet Le Brassus presentation box.
The Audemars Piguet Le Brassus box it arrives in.
Jumbo Proportions, Kept Thin
The case is 39mm across and 8.1mm thick, with a lug-to-lug of about 49mm. Those are the numbers that make a Jumbo a Jumbo: a wide bezel, a slim mid-case, and a bracelet that runs straight off the case with no break. Look at it from the side and you see how flat it really is.
8.1mm from the side, with the AP-signed crown.
On our scale the watch came in at 121 grams, roughly a quarter pound. It sits flat and balanced, and the weight stays even across the case and bracelet.
121 grams on our scale, measurement for reference only.
Caliber 7124, Openworked by Design
Inside is the automatic caliber 7124 with a 57-hour power reserve. This is not a solid caliber with a skeleton dial dropped on top. The 7124 was built to be openworked from the start, with the bridges re-cut so the structure holds while the mechanics show through. It is the openworked version of the current extra-thin automatic that replaced the caliber 2121, the movement that ran the original Jumbo for decades.
The openworked caliber 7124 up close.
A Skeleton Dial You Can Still Read
Skeleton dials can get hard to read. This one stays clear. The outer minute track is clean, and the applied pink gold hour markers and Royal Oak hands sit above the movement with a luminescent coating, so they stand out against the metalwork behind them. You get the openwork and still read the time at a glance.
Pink gold applied markers and Royal Oak hands read cleanly over the openwork.
Bracelet and On the Wrist
The steel bracelet tapers toward a slim, integrated folding clasp, and it holds the unbroken line from case to bracelet that the Jumbo is known for. At 39mm and 8.1mm it wears easy and slips under a cuff, and the openworked dial catches light differently as you move. That is most of the fun of wearing it.
The bracelet runs straight off the case, no break in the line.
On the wrist at 39mm.
Specifications
| Reference | 16204ST.OO.1240ST.01 |
| Case | 39mm stainless steel |
| Thickness | 8.1mm |
| Dial | Openworked, rhodium-toned; pink gold applied markers and hands |
| Movement | Automatic caliber 7124, openworked |
| Power reserve | 57 hours |
| Water resistance | 50 meters |
| Bracelet | Stainless steel with AP folding clasp |
| Weight (measured) | 121 grams |
The reference, size, material, power reserve and water resistance from the video.
What It Costs
Audemars Piguet does not publish US retail, and steel Royal Oak Jumbos have been among the harder pieces to get for years, so they trade at a premium on the secondary market. We have this openworked 50th anniversary example listed at $250,000. We are not financial advisors, and that price reflects where the market sits from what we see day to day, not a promise about where it goes next.
FAQ
What is reference 16204ST?
It is the Audemars Piguet Royal Oak Jumbo Extra-Thin Openworked in stainless steel, released for the Royal Oak's 50th anniversary. The full reference is 16204ST.OO.1240ST.01, and it runs the openworked caliber 7124.
How thin is the Royal Oak Jumbo Extra-Thin?
The case is 8.1mm thick and 39mm in diameter, with a lug-to-lug of about 49mm. On our scale the watch weighed 121 grams. It wears flat and slips under a shirt cuff.
What movement is inside?
An automatic caliber 7124 with a 57-hour power reserve, openworked so you can see the gear train from both sides. You view it through the openwork dial in front and the sapphire caseback in back.
Is it water resistant?
It is rated to 50 meters. That covers daily wear and the occasional splash, but this is a thin dress-sport watch, not a dive watch, so we would keep it away from serious swimming.