If a connoisseur of fine vintage wristwatches was asked to select the most landmark models in the entire history of horology, chances are very high that reference 1518 would be one of the first to be named. This model can be considered a true champion of the field under all the points of view deemed important by a collector: technical proficiency, aesthetic impact, historical importance and rarity.

It is the first serially produced model of the perpetual calendar chronograph with moon phases line of wristwatches, which is now considered one of the true custodians of Patek Philippe DNA. In fact, it is the only set of complications continuously produced by the firm since the 1940s, and all the five representatives of this line are considered absolute icons of watch collecting: ref. 1518, ref. 2499 (1950s-1980s), ref. 3970 (1990s), ref. 5970 (2000s), and ref. 5270 (currently in production). Beyond being the first of them all, the “fifteen-eighteen” is also the rarest of these five references, with an estimated production of 281 pieces overall, so far known in yellow gold, pink gold and stainless steel.

In production from 1941 until 1905s, the case of the model was made by Vichet - one of the historical Patek Philippe case suppliers, most famously employed also for the earliest examples of references 2499 and 2497 - and follows an evolution. Early versions feature the chronograph pushers placed further back on the band, closer to the case back; second series cases, introduced in 1945, instead feature pushers more centrally aligned. The present piece is a not only a very attractive representative of the second series but furthermore one of the earliest examples of this design, as it was manufactured in 1945: the very year of the introduction of the second series.

Last, but most definitely not least, the importance of its absolutely remarkable set of accessories cannot be overstated. The presence of its original warranty Certificate is already sensational: only a very slight minority of the known 1518 examples survived through their 80 years of life together with the document. But the present piece pushes the boundary even further and comes accompanied by the original 1945 Patek Philippe catalogue and price list - both of them extremely collectable items on their own - two original instruction leaflets, documents detailing the service it underwent in the 1980s, and multiple Extract from the Archives.