Patek Philippe launched the Aquanaut in 1997, making it 20 years since this rounded octagonal creation first made waves. Baselworld 2017 ushered in the Aquanaut Travel Time Ref. 5650G "Patek Philippe Advanced Research" in a limited edition run of 500 pieces. It's packed with innovations, such as an open dial to showcase the ground-pushing "compliant (flexible) mechanism in steel", used for setting the second time zone. It’s also the first watch by Patek to combine this feature with a silicon balance spring.