Patek Philippe CHR 27-525 PS Mode D'emploi page 4

Haute horlogerie at its very finest
Patek Philippe's caliber CHR 27‑525 PS is the world's
thinnest split‑seconds monopusher chronograph
movement with column wheel control: it is a scant
5.25 mm thick. Not least, this record was achieved
thanks to an unusual design approach for the conti‑
nuously running 60‑minute counter. This innova‑
tion not only results in a slimmer silhouette, it also
offsets the torque differences between the running
and stopped states of the chronograph.
The three chronograph wheels (driving, clutch, and
seconds wheels) are another exclusive feature of
the CHR 27‑525 PS movement. Their innovative and
patented toothing geometries reduce wear and op‑
timize power transmission within the chronograph
mechanism.
The pinnacle of artisanship
The caliber CHR 27‑525 PS movement is a classic
split‑seconds chronograph construction with
two column wheels that, as always at Patek Phi‑
lippe, are crowned by polished caps. The bridges
à l'ancienne are meticulously chamfered, polished,
and decorated with Geneva striping. Each caliber
is hand‑crafted one by one by a master watchmaker
in the manufacture's Haute Horlogerie ateliers.
Practically every component is individually fi‑
led, chamfered, polished, adjusted, and finished.
Subsequently, the watchmaker performs a trial
assembly, the so‑called repassage en blanc, to ve‑
rify the functional integrity of the movement.
Afterwards, the caliber is completely disassem‑
bled again. When all parts have been cleaned,
they are reassembled, lubricated, and fine‑tuned.
This ancestral method produces horological mas‑
terpieces that exceed the expectations of even
the most discerning aficionados.
A paragon of style
To complement the bright luster of the polished
steel case, Patek Philippe designed an iridescent
silvery dial with a railway track minute scale that
underscores the masculine, technical look of the
split‑seconds chronograph. The delicate black‑
lacquered engravings in the corners of the dial are
unique signature elements. The cushion‑shaped
sapphire‑crystal glass is gently cambered, as is the
display back that affords a stunning view of the
movement and the satin‑finished surround with its
gold‑filled engravings. The sapphire‑crystal back
can be replaced with an interchangeable solid steel
back that comes with the watch.