Patek Philippe CALIBER 240 HU LU Manual Del Usuario página 16

The stationary disk above it is the so-called mask
16
with precisely calculated contours; with remark-
able accuracy, it exposes the visible portion of
the moon, replicating its progression day by day.
Thanks to a highly complex and innovative metal-
lization technology, the moon presents an almost
photorealistic face against the backdrop of the star-
studded nocturnal sky. Moreover, the moon-phase
display mechanism is extremely accurate; it devi-
ates from the true lunar cycle by merely one day
every 122 years.