The Ref. 5990/1A-011 Nautilus Travel Time chronograph is one of Patek Philippe’s rare steel watches. It features a new blue dial with a ray sunburst dial and a delicate black gradation to the periphery. The self-winding calibre CH 28-520 C FUS movement combines three convenient and user-friendly complications: a flyback chronograph, a Travel Time function (two time zones with two separate hour hands; the skeletonized hand shows home time) and an analog date at 12 o`clock which is synchronized with local time.