This watch is also known as:
5002P/001 , 5002P-001 .
The Sky Moon Tourbillon Ref. 5002 is the most complicated wristwatch ever produced by Patek Philippe and also the workshop's first double-face wristwatch. Its movement consists of 686 parts, some of which are microscopically small. Minute repeater with tourbillon escapement Chime with two ?cathedral? gongs activated by a slide piece in the case Front side: Perpetual calendar with retrograde date hand Hours and minutes of mean solar time Day, month, leap year by hands Moon age Crown at 4 o'clock: setting of the time and winding Opaline-white dial with embossed Calatrava cross motif, gold applied Roman numerals 9 hands Reverse side: Sidereal time, skychart, phase and orbit of the moon Crown at 8 o'clock (24-hour scale): correction of sky/moon indications Case is humidity and dust protected only (not water resistant) Case diameter: 42.8 mm