Patek Philippe Retrograde Perpetual Calendar 5059G Officer Case in 18k White Gold with Original Certificate of OrigineIntroduced in 1998, Reference 5059 was the first serially produced perpetual calendar wristwatch with a retrograde date ever made by Patek Philippe. It was also the first perpetual calendar model since the legendary References 2497 and 2438 1 to feature a sweep centre seconds hand. The watch is distinguished by its 36 mm officier style case, with elongated lugs secured by screwed bars, as well as a hinged case back incorporating a display window and