Today, we bring you our hands-on review of the exceptional Patek Philippe Annual Calendar Chronograph ref. 5960/1A. When the ref. 5960P was first launched in 2006, this reference 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 rose gold. Now, the letter 'A' in the model designation 5960/1A —which stands for 'acier', steel in French—, announces a paradigm change. The Annual Calendar Chronograph in stainless steel is not only the latest sibling of its lineage but had also replaced the gold and platinum versions.