The Patek Philippe Reference 5711/1A Nautilus is a classic elegant sports watch. The inspiration for the Nautilus comes from the universal shape of a porthole found on virtually all maritime vessels. The Nautilus Ref. 5711/1A in steel, has a case diameter of 43mm, one millimeter larger than the original Nautilus Ref. 3700/1. It’s dial displays the hours, minutes, sweep seconds and the date in a window at 3 o’clock.