Patek Philippe has long been known as a producer of some of the finest watch movements known.
Most Patek Philippe calibres carry a numeric identifier. When identifying a movement, it is common only to refer to the number and any prefix. For example, Calibre R 27 PS QR would be referred to as “Calibre R 27” generally, while Calibre 324 S C might typically and properly be called “Calibre 324” or “PP 324”.
Most historic Patek Philippe movements are identified by a two-part number. The first part was the size of the movement, first in ligne and later in millimeters with the second being a unique calibre number. For example, Cal. CH 28-520 C is a 28 mm chronograph movement and Cal. 10-200 is 10 ligne across.
Today, Patek generally uses simply a model number as the base indicator, though most of their chronograph calibres and historic pieces still use the old “dash” nomenclature.
Historically, Patek Philippe would also add a numeric indicator of the module added for complications, such as 315/290.
However, in recent decades, the company has taken to using a number of alphabetical abbreviations indicating the complications present. Note that Patek does not always indicate every complication present but only the most notable and distinctive to this particular calibre.
|C||Representatives calendar“||Date window or pointer|
|FUS||Double Fuseau”||Dual time display|
|HU||Heure Universelle“||World time indicator|
|IRM||Indicateur de Réserve de Marche”||Power reserve indicator|
|LU||Phases de Lune“||Moon phase|
|PS||Petite Aiguille de Seconde”||Small seconds|
|Q||Quantième Perpétuel“||Perpetual calendar|
|QA||Quantième Annuel”||Annual calendar|
|QI||Quantième Perpétuel Instantané“||Perpetual calendar with instant change|
|QR||Quantième Rétrograde”||Perpetual calendar with retrograde date indicator|
|R||Répétitions minutes“||Minute repeater (typically listed before the calibre number)|
|REG||Affichage de Type Régulateur“||Regulator configuration|
|S||Seconde au Centre”||Central seconds|
|SAV||Savonette“||Savonette or hunter configuration|
|SID||Temps Sidéral”||Sidereal time|
|TO||Tourbillon”||Tourbillon (typically listed before the calibre number)|
|8J||8 Jours“||8-day power reserve|
|24H||Indication 24 Heures”||24 hour or 12-hour plus day/night indicator|
Patek Philippe's first automatic watch movement, Cal. 12-600 AT, is also one of its best. Introduced in 1953 and improved (as Cal. 27-460) in 1960, this movement lasted in production for 32 years. Its successor was the micro-rotor Cal. 240, introduced in 1977 and still in use today.
The quest for a thinner and simpler movement has not been so straightforward. Patek Philippe tried peripheral rotor technology with the ill-fated Cal. 350 before turning to Jaeger-LeCoultre to supply a replacement, Cal. 28-255. This was replaced by Cal. 335, another in-house disappointment, which was quickly refined and replaced by Cal. 315. It was not until the 2004 introduction of Cal. 324 that Patek Philippe could claim to have a solid high-beat “workhorse” automatic movement of their own.