In 2006, Patek Philippe released the reference 5800/1A-001 , exclusively in steel - featuring an automatic 330 calibre (SC) and ‘ridged' blue dial, with horizontal grooves. The 5800 marked the return of the mid-size Nautilus, previously discontinued in the early 2000s (as the ref. 3800). Examples of the reference 5800 were produced for a limited time (approximately one year), representing an exceptionally rare and highly-collectable modern Patek Philippe.
The 5800 re-interprets a number of signature design elements from the original Nautilus - mostly notably, the monobloc case construction with integrated sapphire caseback - the only reference from the modern collection (2006) to do so. Similar to its earlier, mid-size predecessor, the 5800 measures 38.4mm (up from 37.5mm), comfortably suited to most wrist sizes. The steel, two-piece case provides water resistance up to 120m, further featuring a screw-down crown.
This steel Nautilus 5800 watch is the perfect balance between utilitarian function and elegant design. The case and bracelet are excellently finished, with beveled, polished and granular surfaces. The steel bracelet has virtually no stretch. At 37.5 mm in diameter, and only 7.8mm thick, the 5800 case is a unique twist of perspectives and size. The ‘ridged’ blue dial includes all the traditional indications of a time-only watch, with applied hour-markers and Nautilus hands (with luminous inserts).
The reference 5800/1A-001 is powered by Patek Philippe’s in-house calibre 330 SC, visible through the sapphire display-back. It features 29 jewels, a straight-line lever escapement, shock absorber mechanism a self-compensating flat balance spring and a monometallic balance, adjusted to cold, heat, isochronism and 5 positions. Furthermore, the solid-gold rotor is finished in classic Patek Philippe style, with circular Geneva stripes.