'Most complicated wristwatch ever' to sell for $1.3m
Patek Philippe's masterpiece watch will be available for sale and public viewings in New York this month
"The most complicated wristwatch ever produced," by legendary watchmakers Patek Philippe is sent to go on sale on October 7.
The sale will take place at Patrizzi and Co's Madison Avenue showroom in New York City as part of their Important Pocket Watches, Wristwatches and Clocks sale.
The Sky Moon Tourbillions watches are expected to sell for about $1.3m each.
Why is the watch so complicated?
Well, the double-faced Sky Moon Tourbillion doesn't just count the seconds, minutes and hours - it keeps track of the stars as well.
The watch is crafted out of 18-karat yellow gold, and features a sky chart on the reverse side of the black dial that tracks sidereal time.
Sidereal is used by astronomers to track of the direction in which their telescopes need to be pointed to view chosen stars - which rise in the east and set in the west - in the night sky.
A public previewing of the watches will be held in the showroom on October 3, 5 or 6.