PATEK PHILIPPE | NAUTILUS, REFERENCE 5990, A STAINLESS STEEL DUAL TIME ZONE FLYBACK CHRONOGRAPH BRACELET WATCH WITH DATE, CIRCA 2014 | 百達翡麗 | "Nautilus 型號5990 精鋼兩地時間飛返計時鏈帶腕錶，備日期顯示，機芯編號5800989，錶殼編號6013193，約2014年製"

The Patek Philippe reference 5990 made its debut in 2014. The story actually starts almost a decade earlier though. In 2006, Patek Philippe celebrated the 30th anniversary of the Nautilus collection. To mark the occasion, the original design by Gerald Genta from 1976, was updated ever so slightly.

This model is only available in steel and only with a gradient grey dial. It features the familiar horizontally embossed Nautilus pattern. As well as the central dual time display, the date is shown on a sub-dial at 12 o’clock. This is linked to the local time display. The ten gold applied hour markers and local hour and minute hand have a luminescent coating. The day/night indicators are positioned below the center axis. The one for local time is at 9 o’clock. The one for home time is at three o’clock. These show white for day and blue for night.