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You are here: Home / Movements / AP 2120

AP 2120

Last Update: December 12, 2019

Brand:Audemars Piguet, Jaeger-LeCoultre
Family:
JLC 920 Family
Height:2.45 mm
Jewels:36
Reserve:40 hours
Frequency:19,800 A/h
Winding:Automatic, Bi-Directional Automatic Winding, Central Rotor Automatic Winding
Diameter:28.40 mm (12.5 ligne)
 © Audemars Piguet Complications:
Hands:Central Hour Hand, Central Minute Hand
Distinguishing Technical Characteristics
Ultra-Thin Central-Rotor Automatic
Central-Rotor Automatic
Counter-Clockwise Balance Cock
Gyromax Balance
Balance
Balance at 6:00
Central Rotor
Production: 1967 – Current
1910s 1920s 1930s 1940s 1950s 1960s 1970s 1980s 1990s 2000s 2010s 2020s

Cal. 2120 is an ultra-thin automatic movement from Audemars Piguet, developed by Jaeger-LeCoultre and introduced in 1967. Audemars Piguet continues to rely on Cal. 2120 and the similar Cal. 2121 as of 2019.

Jaeger-LeCoultre developed their Cal. 820 for high-end clients, Audemars Piguet, Patek Philippe, and Vacheron Constantin. Although given a JLC movement number, it was never used by the parent company. Each company decorated and finished their own movement and assigned it their own movement number. Patek Philippe stopped using the movement in the 1980s, and Jaeger-LeCoultre ceded the rights to Vacheron Constantin and Audemars Piguet when they became part of Richemont in 2000.

© Audemars Piguet

Cal. 2120 achieves its remarkable thin profile thanks to some innovative features. The rotor rides on four peripheral ruby bearings or runners rather than central ball bearings. The mainspring barrel is said to be “flying” because it is anchored only on one side.

When it was first delivered in 1967, Cal. 2120 was equipped with a Patek Philippe-style Gyromax balance and free-sprung flat hairspring. Later, Cal. 2120/1 was introduced with a Glucydur annular balance and more traditional regulator. Another development on this base was Cal. 2121, which adds a date mechanism and remains in production today.

Because it is a reliable and thin movement, it is the basis for many complicated movements.

  • Audemars Piguet Cal. 2120/2802 – Perpetual calendar and equation of time
  • Audemars Piguet Cal. 2120/2808 – Perpetual calendar and equation of time
  • Audemars Piguet Cal. 2120QP – The world’s thinnest automatic perpetual calendar when introduced in 1978
  • Audemars Piguet Cal. 2121 – Automatic with date
  • Audemars Piguet Cal. 2122 – Automatic with date and center seconds
  • Audemars Piguet Cal. 5122 – Automatic with date

Audemars Piguet still uses Cal. 2120 as of 2019:

  • Audemars Piguet Jules Audemars Extra-Thin, Ref. 15180
  • Audemars Piguet Tradition Extra-Thin, Ref. 15160, 15337
  • Audemars Piguet Royal Oak Tuxedo, Ref. 15154
Images are taken from official publications and are used here for commentary and educational purposes. Copyright is held by the original owner as noted.

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