The Patek Philippe Calatrava is a line of dress watches built by the premier Swiss watchmaker Patek Philippe, introduced in 1932. The Calatrava has become the signature model for Patek Philippe since its creation in 1932; its understated style has made it a timeless classic, providing subtle elegance from generation to generation. These pre-owned Calatrava models with the reference number 3520 are supplied with a year warranty.