Introduction
While Audemars Piguet is best known today for the Royal Oak, the Le Brassus manufacture spent much of the twentieth century producing some of the finest ultra-thin dress watches in Swiss watchmaking. Elegant, understated and technically accomplished, these references showcased the brand's mastery of refined movement construction long before the Royal Oak became its defining icon.
Produced during the 1960s, the ref. 5091BC embodies that philosophy perfectly. Its beautifully proportioned 18K white gold square case measures just 25.5mm across and an astonishing 4mm thick, housing the legendary manual-wind calibre 2003, one of the thinnest mechanical movements ever produced. Offered here in excellent condition and accompanied by its original 18K white gold Audemars Piguet buckle, this is an increasingly scarce example of one of AP's most elegant and overlooked vintage dress watches.
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Grade
V 8.5
Status
Vetted & Approved
Included
Watch Only
Est. value range
$3,000 – $5,000
The Details
Brand
Audemars Piguet
Dimensions
25.5mm
Model
Classique Ultra-Thin
Movement
Manual-wind Audemars Piguet cal. 2003
Reference
5091BC
Bracelet
Leather strap
Year
Circa 1960s
Condition
Excellent
Material
18K White Gold
Included
Watch only
Dial Color
Silver
THE CONSTRUCTION
Crafted from 18K white gold, the beautifully proportioned square case measures just 4mm thick, giving the watch an exceptionally refined wrist presence. It retains its crisp edges, sharp geometry and strong hallmarks, qualities that are increasingly difficult to find on vintage dress watches.
THE MOVEMENT
Powering the watch is the celebrated manual-wind calibre 2003, one of the thinnest mechanical movements ever produced. Its remarkable slimness allowed Audemars Piguet to create dress watches of extraordinary elegance while maintaining the exceptional finishing standards expected from the manufacture.
TIMING MACHINE READOUT
This reading was taken (crown down) with a ONEOF Accuracy Boutique Edition timing machine at time of cataloging. It is provided as a courtesy only, and shall not be construed as a warranty or guarantee of any kind. Please refer to our terms and conditions of sale for more information.
Condition
Watch is in overall excellent condition. The 18K white gold case remains well defined and shows surface scratches and scuffs consistent with the watch's vintage character, along with a few small nicks where the case back has been removed. The hallmarks on the case side and the stamp on the case back remain excellent. The dial shows some light surface marks and has developed a uniform patina, while the hands remain clean. It is fitted with a black leather strap and an 18K white gold Audemars Piguet pin buckle showing light surface scratches.
Please note: The watch ticks at the time of cataloging, but timekeeping is poor and a service is recommended.
Our Perspective
Before the Royal Oak transformed Audemars Piguet, the manufacture quietly built its reputation on elegant ultra-thin dress watches such as this. Powered by the legendary calibre 2003 and housed in a beautifully preserved unpolished white gold case, the ref. 5091BC offers collectors an opportunity to own one of the purest expressions of mid-century Audemars Piguet design.
Eric Ku
Co-founder
