Second Series 3971EJ Patek Philippe Perpetual Calendar Chronograph

Where you see feuille hands on a 3970, you know you’re talking early series and immensely collected watches today. But this isn’t a 3970. It’s a 3971, a reference created before the standardization of selling both a solid and sapphire caseback with each 3970. The 3971 was a screwdown, sapphire-backed, equivalent of the 3970 made from 1986 until ~1990 until it became standard practice to include both casebacks under one reference. They are some of the most desirable 3970-adjacent watches made, as they combine the best of second series good looks with the later-production ability to ogle your calibre CH 27-70 Q in admiration. And it’s a big hallmark.

As mechanical watches rose back to prominence in the early 90s, demand for exhibition backs exploded. The first series of 3970 began as a snap back, largely solid. But client demand meant that sapphire snap casebacks were also made under 3971 from the very start in 1986. This practice continued into the second series, ending in the third series near 1990 when both backs became standard. The second series is widely estimated to have been made in 650 examples across all metals and backs. Of these, 150-200 are estimated to be 3971 (One aside: 3971 is often conflated with the integrated bracelet model, but that’s ref. 3970/2). In second series there’s also a huge range of how hallmarks can appear. The very chronological center of second series saw a narrow window of oversized ‘big’ hallmarks appear on the lug outer, punched twice as large as normal. Most have small hallmarks and collectors increasingly love these oversized, almost absurd ones.  

The 3970 has finally begun to be seen as a vintage watch, and values are climbing more quickly than they ever have historically. The PCC is Patek Philippe’s flagship. Even if not the most complicated watch they’ve made, the PCC defines the public perception of any era of Patek Philippe. Philippe Stern’s tenure of the brand is finding favor now more than ever for its austere, proportional, and balanced designs. The 3970 is no longer ascending to be considered as one of the all-time great Patek Philippe references, it’s now in those halls alongside a 2499. And when one considers the relative value here, well, it’s easy to see how these have a ways to run—particularly the first two series which are undeniably as beautiful and rare a PCC as has ever been made.

This example is fantastic overall. The case may have seen a very very light polish but wear like you see on the Key 28 can occur from just normal day-to-day wearing. The steps are proud and not rounded, the lug junctions are strong as well. Its dial shows no signs of damage or marking. All is lovely. It comes with an Extract dating it to 1990, from a well-regarded Zurich retailer.