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 caliber 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.

Sunburst blue with black-gradient rim, horizontally embossed, gold applied hour markers with luminescent coating. Steel. Case diameter (10 - 4 o’clock): 40.5 mm. Height: 12.53 mm. Screw-down crown. Water-resistant to 120 m. Sapphire crystal case back. Steel. Patented fold-over clasp with lockable adjustment system. Flyback chronograph. Central chronograph hand. 60-minute counter. Two time zones: local and home time indication. Day/night indication for local time and home time in apertures. Date coupled with local time by hand.

Flyback chronograph. Central chronograph hand. 60-minute counter. Two time zones: local and home time indication. Day/night indication for local time and home time in apertures. Date coupled with local time by hand. Diameter: 31 mm. Thickness: 6.95 mm. Number of parts: 370. Jewels: 34. Power reserve: min. 45 hours - max. 55 hours. Winding rotor: 21K gold central rotor. Balance: Gyromax^®. Frequency: 28,800 semi-oscillations per hour (4 Hz). Balance spring: Spiromax^®. Hallmark: Patek Philippe Seal.