Pulled from the steel lineup and never replaced, the first Aquanaut Patek Philippe ever built with a complication has quietly become one of the hardest modern references to actually find. Casual enough for a Saturday, serious enough that every collector in the room knows exactly what it is. Built for the guy whose passport sees more action than his suit jacket.

Presents itself in mint condition with little to no signs of wear. Embossed with the pattern that started the whole family, the black dial throws a warm copper glow the second direct light hits it, then drops back to stealth black when you turn away. Carved into a soft octagon, the stainless steel case plays satin brushing against mirror polished bevels, and those edges are still as crisp as the day they left Geneva. Wrapped in the tropical textured rubber Patek designed for this family alone, the strap carries its own checkered relief straight off the dial and onto your wrist.

Functions include hours, minutes, seconds, date, second time zone, and separate day and night indication for local and home time. The screw down crown on the right side unlocks counterclockwise, winds the movement in its first position, and sets both hour hands together when pulled out to its second position. Two pushers sit on the opposite flank, and the upper one jumps your local hour hand forward a full hour while the lower one walks it back, all without disturbing the skeletonised hand holding your home time. The recessed corrector at four o’clock advances the pointer date across the globe subdial, and a Patek setting stylus is the only tool that should ever touch it. After a month at rest, wind it fully, set the date to yesterday, then run the hours forward until today flips over and the correct time lands, and note that the sweeping seconds hand keeps running with the crown out because the self winding caliber 324 S C FUS, good for roughly forty five hours and sealed to one hundred twenty metres, was built without a stop seconds.

Comes as a complete set, double boxed with certificate of origin, leather document folio, caliber 324 self winding movements booklet, and collector’s library booklet.

Steel Pateks that carry a complication make a very short list, and this one sits at the top of it for anyone who actually travels. For the collector who already owns the dress watch and the diver and wants the piece he can wear from a red eye straight to a rooftop without thinking twice, few things do the job this cleanly. Ones like this tend to move quietly, and the ones that get away have a way of staying gone.