Patek Philippe is presenting this Calatrava "Squelette" for the 40th anniversary of its extra-thin 240 automatic calibre. Part of the brand's regular collection since 2008, it appears here in a new 5N 18k pink gold version. Traditional hand-skeletonising and hand-engraving confer full elegance on the mechanism. The plate and bridges are cut away within the very limits of possibility to allow a clear view of the movement without compromising any of its reliability. The parts are then passed to the engraver. Lastly, the movement chassis is entirely plated with pink gold. The ring surrounding the movement, also in pink gold, is skeletonised to leave just twelve spokes which serve as hour markers.