Only released as recently as 2012 this handsome, and robust, piece was Rolex's first completely new model in 20 years. A travellers timepiece, not unlike the GMT -Master, the Sky-Dweller displays the time in two time zones simultaneously but this time with use of an off-centre rotating disc within the dial itself. At its heart there is Rolex's own patented annual calendar mechanism which displays the month of the year by highlighting one of 12 small apertures ,in red, around the dial. This mechanism automatically knows how many days are in each month.