When one of the major introductions from Patek Philippe is crafted from stainless steel, it is almost always a sports model. But every rule needs to have an exception. In the past, Patek Philippe has veered a few times off the precious metals, towards the more common steel for their classic watches, but only on rare occasions. That is one part that makes the 5212A Calatrava Weekly Calendar so special, as the other part is the complication that it is fitted with!