The 5270G-018 is a watch that separates Patek Philippe from many other high end manufacturers. A perpetual calendar chronograph is a rare complication due to its complexity and creating a legible dial to display the information at hand is essential. The layout is a typical combination of calendar and chronograph with pushers at 2 and 4 o'clock positions. The only indication that the watch is perpetual is a small aperture to the right of the moon phase sub dial showing the progress of the leap year cycle. At 41mm in diameter the watch is on the large-side for Patek but absolutely perfect for the job in hand and a comfortable fit for all wrists. One of the finest watches produced and a future collectable.