The dial is where this watch earns its reputation. It uses Patek Philippe’s signature embossed grid pattern, and depending on the lighting it can shift from a deep black to a warm brown gradient, which is exactly why you often see it described online as both a black dial watch and a brown dial watch. Large luminous Arabic numerals sit on brushed applied indices, and the layout is kept clean despite the added complication.
At 9 o’clock you find the LOCAL indicator, and at 3 o’clock the HOME indicator, each with a small day and night window. This lets the wearer track two time zones at a glance, which is the entire point of a travel watch. Below the center of the dial sits a sub dial with a subtle embossed globe pattern and the date track, a small design touch that ties the whole travel theme together.
The case measures 40.8 millimetres, finished in the rounded octagonal shape that Gerald Genta originally sketched out for the Nautilus and that later became the Aquanaut’s own identity. Two correctors sit on the left side of the case at 8 and 10 o’clock, allowing the local hour hand to jump forward or backward in one hour increments without disturbing the running seconds or the home time display, a genuinely clever and practical piece of engineering.
The strap is what Patek Philippe calls the Tropical strap, made from a composite material that resists saltwater, UV exposure, and everyday wear far better than a standard rubber strap. It closes with the folding clasp stamped with the Calatrava cross, the brand’s own crest, which you can see clearly on the crown and clasp in the photos.
Inside, later production of the 5164A-001 runs on the upgraded Caliber 26 330 S C FUS movement, an automatic self winding movement built specifically for the Travel Time complication, offering a comfortable power reserve and the smooth, reliable jumping hour function that Patek Philippe travel watches are known for.