Aquanaut Travel Time Ref. 5650 showcases an aesthetic and functionality along both axes with similar symmetry to its predecessor Aquanaut Travel Time Ref 5164. It also shows the times of two different cities with the use of two-hour hands and depicts day from night with an aperture for each.
However, Patek Philippe made two main improvements to the Aquanaut Travel Time Ref. 5650; a new hairspring design and a new flexible mechanism in traditional steel. Flip the watch around and you are able to see the change in the hairspring design with a new Spiromax balance spring that is still silicon but has a different geometry. Its new flexible mechanism is showcased by an opening on the left side of the watch. This mechanism is based on the flexibility of materials. In the Ref. 5650, it is used to adjust the local time’s hour hand and allows for fewer parts to be used and a reduced height, which helps eliminate friction that causes wear and tear.