Patek Philippe Grand Complications Perpetual Calendar Moon Phase Watch - 5140P-01737. 2 mm platinum case, interchangeable full back and sapphire crystal case back, charcoal gray sunburst dial with gold applied hour markers, caliber 240 Q self winding movement with perpetual calendar (day, date, month, leap year by hands, moon phases, 24 hour dial), approximately 38 48 hours of power reserve, shiny black alligator strap with square scales, fold over buckle. Water resistant to 30 m.