The Annual Calendar Chronograph created in 2006 by Patek Philippe, the first automatic chronograph in the history of the Manufacture, now comes in a steel case with a matching bracelet composed of drop-shaped links. This is a surprise from the Fine Watchmaking brand most keenly sought after by collectors, which rarely uses this metal and is doing so as part of its 175^th anniversary celebrations. The watch acquires a resolutely sporting character reinforced by red and black accents sprinkled across the dial. The hour-markers as well as the hour and minute hands have been redesigned to give them a far more noticeable presence. While the previous annual calendar configuration has been maintained, with the day, date and month appearing in three large apertures, the mono-counter chronograph function has been rearranged in such a way that the hours totalizer now appears around the two minute totalizers. The column-wheel movement is naturally visible through a sapphire caseback.