Patek Philippe Perpetual Calendar compactwidth several different manufacturers supplied these

several different manufacturers supplied these watches according to MOD standards

blued-steel 'sword' handset and matching oversized sapphire cabochon crown

It mandated an entirely new manufacturing process to achieve the satin finish across its sloping case curves and polished accents along its sharper edges

the inspiration for the model’s nomenclature)

and corrector pushers located along the case flanks

Patek Philippe Perpetual Calendar compactwidth several different manufacturers supplied theseA perpetual calendar is like a small computer on your wrist. Think of it this way: Imagine a watch that keeps track of not only the time, but also the date, the day of the week, and the month, and also tells you whether its a leap year or not, and what the current phase of the moon is. Oh, and one more thing imagine it does all of this mechanically, using springs and gears, and that you only have to adjust it once every century or so. Crazy, right?