The star of the GMT XXL Swiss edition of which it graced the cover page, the reference 5123 celebrates the 80^th anniversary of the legendary Calatrava and symbolises the passing on of the torch between Philippe Stern and his son Thierry at the helm of the prestigious Geneva-based watch company. Loyal to the House philosophy of delighting fine watchmaking connoisseurs with timepieces that are as slender and elegant as possible, this new release for 2012 takes the shape of a two-part case that is extremely complex to make and inspired by a 1950 Calatrava. The upper part plays the role of a bezel to fix the sapphire crystal which is convex on both sides, while the inner part incorporates the sapphire crystal and the strap attachments so that the strap bars almost entirely disappear beneath the case. Aesthetes will note this detail that highlights the perfect circle of the case due to the absence of any gap between the ends of the strap and the patiently polished rose gold case. This understated masterpiece, with its dial exclusively dedicated to the passing of time, is endowed with extreme precision and reliability thanks to the legendary Manufacture Patek Philippe Calibre 215 PS, of which the 130 parts are entirely crafted and assembled according to the standards laid down by the Patek Philippe Seal.