Patek Philippe launched the Nautilus in 1976 to compete against the uber-successful Royal Oak from AP which had been released 4 years prior. Patek used the shape of a porthole as a reference when it designed the Nautilus, and just like Captain Nemo’s ship the Nautilus is a powerful machine able to take you 20,000 leagues under the sea and beyond.
The Nautilus, reference # 5726A-001, is made in stainless steel which has been both brushed and polished underlining Patek’s obsession with detail. The porthole shaped case carries a case diameter of 40.5mm, which sits very neatly on the wrist. The bezel is prominent and is faceted adding a utilitarian edge to this refined timepiece. The main crown fits neatly into the bezel lug on the right side. The main crown is screw down, which maintains maximum water resistance. This Nautilus model carries a water resistance of 120 meters (12 ATM).
The case back carries an exhibition sapphire crystal, where one can admire the majesty of the mechanical self-winding movement Caliber 324 S QA LU 24H. The power reserve on this model comes in at a minimum of 35 hours and a maximum of 45. The Gyromax balance wheel vibrates at a constant 28,800 VpH or 4 Hz. The oscillating weight is in gold and is ribbed with Cotes Circulaires, which has been engraved with the Patek Philippe emblem. The movement bears the noteworthy Patek Philippe Seal.
The grey dial features horizontal striated guilloche pattern with rhodium colored indexes and hands. Both the indexes and hands are coated with luminescence for enhanced readability under low light conditions. At the 6 position is a 24 hour subdial, which also incorporates a 29 ½ day moon phase display. Where the index at 6 should be located, there is a neat date aperture in its stead. At the 12 position carries another dual aperture indicating the day and month. This model uses a central sweep seconds hand.
The 5726A-001 is fitted with a black alligator leather strap with rectangular scales, and it features contrast stitching in grey complementing the dial. This leather strap is secured by a folding clasp made from stainless steel.