The IWC Perpetual Calendar Double Moon is by far one of the most complex-faced watches I personally have ever seen, there are so many features that are all displayed on the dial of this watch such as a Perpetual calendar with displays for the date, day, month, year in four digits and perpetual moon phase for the northern and southern hemisphere, one would think it would be overwhelming in design. But in reality, everything blends seamlessly in an alchemy of function and form with the IWC, even the rose gold casing against the black dial upon the dark brown/chocolate alligator/crocodile skin strap. 

Rose gold has to be one of the most striking metals for watches out there. IWC constructed this case with the finest of 18k rose gold all throughout and even through the buckle on the crocodile strap that comes standard with these watches. Even in the interior, there is 18k rose gold in the way of the Arabic numerals and hands against the black dial and numerous perpetual calendar features. This specific watch is USED but was worn with care, it comes with a full box and authentication papers, as well as a green rubber strap.

This is an 18K rose gold IWC Portuguese Perpetual Calendar, IW503202. It has an alligator leather strap with a matching 18K rose gold deployment buckle, scratch resistant sapphire crystal. The solid 44.2mm diameter three-body case, downturned lugs, and stepped angled bezel are polished; the transparent skeleton display sapphire case back is secured with 6 screws.

The dial is black with rose gold feuille hands and applied Arabic numeral hour markers and outer dot minute markers. There is a subsidiary dial for the small seconds and the day of the week at 9 o'clock, a dial for the month at 6 o'clock, and a Northern and Southern hemisphere moon phase display at the 12 o'clock position. There is a 7-day up-and-down indication sub-dial at 3 o'clock, and an aperture window for the 4-digit year is between 7 and 8 o'clock.

It's water resistant to 30 meters/100 feet, and it has a power reserve of 7 days at full wind. The 15.5mm thick case, dial, and movement are all signed. The automatic self-winding IWC caliber 51614 movements are rhodium plated with fausses cotes embellishment. It's constructed with 62 jewels, a shock absorber mechanism, and a straight-line lever escapement. It has a monometallic balance that's adjusted to 5 positions, a self-compensating Breguet balance spring, and a micrometer regulator. The mechanism oscillates at a frequency of 28,800 vph (4 Hz). The skeletonized rotor contains the gold medallion inlay engraved "IWC - Probus Scafusia."