The Annual Calendar Chronograph in platinum was the first automatic chronograph from Patek Philippe when it premiered back in 2006. Now the brand’s released the Reference 5960/A1, making it one of the very few Patek timepieces in steel outside its sports watch collection. It still features a monocounter and calendar display in three large apertures, while the layout of the monocounter scales has been changed. You’ll notice a 12-hour totaliser around the outer edge, a 0 to 30-minute totaliser in the middle, and a 30 to 60-minute totaliser in the centre. The automatic CH 28-520 IRM QA 24 calibre, with column wheel and disc clutch, also drives a day/night indication at 6 o’clock. The Patek Reference 5960 delivers 28,800 vibrations per hour with a power reserve of atleast 45 hours.