With Patek Philippe Extract from the Archives confirming production of the present watch in 1942 and its subsequent sale on July 31st of the following year.
In 1941 Patek Philippe introduced the reference 1518 to the market. This now treasured and collectible timepiece was the first perpetual calendar chronograph wristwatch to be manufactured in series by any firm in the world and remained in production until 1954 when it was succeeded by the reference 2499. Only 281 examples of this renowned wristwatch were made in total.
Examples of the reference 1518 are illustrated in Patek Philippe Wristwatches by M. Huber & A. Banbery, First edition, page 231 plate 386, and Second Edition, page 303, plate 459