When it was launched in 2006, the Patek Philippe Annual Calendar Chronograph in platinum won instant acclaim. It was the manufacture's first self-winding chronograph, manifested a new and unique style with its prominent monocounter and three large calendar apertures, and quickly established itself as one of the most coveted timepieces of the Patek Philippe portfolio. The success story continued with further versions in platinum and rose gold. With the release of the stainless steel reference 5960/1A —which you can read about it here— in 2014, the platinum model was officially discontinued.