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Zenith 133
Automatic · 13‴ · Switzerland · 1948
Dimensions
30 mm
Height
4.90mm
Jewels
20
Power reserve
35h
Timegrapher
Beat rate
18,000bph
Frequency
2.5Hz
Reference: healthy amplitude ≈ 270–315° fully wound (>200° at 24 h); beat error ideally < 0.5 ms.
Movement
| Movement type |
Automatic
Mechanical movements fitted with an oscillating rotor that winds the mainspring through the wearer's natural motion. Invented by Abraham-Louis Perrelet around 1777 for pocket watches and adapted to the wristwatch by John Harwood in 1923, it combines traditional craftsmanship with everyday convenience.
|
|---|---|
| Winding type |
Automatic (Rotor-Driven)
Self-winding via a rotor whose motion winds the mainspring through a transmission gear train. The specific rotor configuration (central, micro, peripheral, bumper) is catalogued separately under Rotor Type. Standard on the vast majority of mechanical wristwatches since the mid-20th century.
|
| Setting type |
Stem Set (Crown Pull)
The dominant modern system: pulling the crown out to a setting position engages the hand-setting mechanism. Introduced in the late 19th century and refined into multi-position crowns (date, time, GMT). Used in virtually all modern wristwatches and most 20th-century pocket watches.
|
| Escapement type |
Swiss Lever
The undisputed standard of modern mechanical watchmaking. Through an elegant interplay between escape wheel, pallet fork, and balance, it delivers reliable impulses with the safety of 'draw' to keep the lever locked. Refined since the 18th century, it powers almost every quality mechanical wristwatch made today.
|
| Control type |
Balance Wheel
The heart of mechanical timepieces, the balance wheel is an oscillating component that, together with the hairspring, forms a harmonic oscillator regulating the gear train's pace. Its steady back-and-forth motion ensures the even release of energy from the mainspring, governing the watch's accuracy.
|
| Regulator type |
Pinned Regulator (or Index Regulator)
The most traditional regulator, consisting of a movable index pointer fitted with two curb pins (or a pin and a boot) that embrace the hairspring. Sliding the index along its scale changes the spring's active length, adjusting the rate. Simple, reliable, and easy to service, it remains the workhorse standard across countless mechanical movements.
|
| Rotor type |
Hammer (or Bumper) Rotor
An early automatic design where the rotor swings back and forth within a limited arc, striking small spring buffers at each end (hence 'bumper'). Introduced by John Harwood in 1923 and used in vintage calibres from Eterna, Felsa, JLC Futurematic, and early Rolex Oysters. Largely superseded by full-rotation rotors after 1948.
|
| Shock protection |
Incabloc
The most famous and widely used shock protection system in horology. Invented in 1934 by Georges Braunschweig and Fritz Marti at Universal Escapements (La Chaux-de-Fonds), it employs a lyre-shaped spring holding the jewel setting, allowing it to shift under impact and return to position. Adopted by countless Swiss makers across the 20th century.
|
Specifications
| Lignes | 13‴ |
|---|---|
| Shape |
Round
It is the most common form that we can find.
|
| Complications |
Sweep Second
Contrary to the ticking motion of quartz watches, the sweep second hand in mechanical watches moves smoothly around the dial, offering a visual representation of time flowing continuously. This has become synonymous with the precision and craft of mechanical horology.
|
| Hand count | 3 |
| Hand sizes | 1.70 x 1.20mm |
Origin & References
| Manufacturer | Zenith |
|---|---|
| Country | Switzerland |
| Launch year | 1948 |
| COSC certified | No |
| Signature | 1959: 4767699, Zenith, Swiss Made, 20 Jewels; Incabloc
(Zenith 133.8; 21600A/h) |
| US import codes |
|
Notes
Remarks: 1948-1951, 25000
Other data: balance staff: U2217 stem: W2363 mainspring / battery: 1.20 x 10.0 x 0.08mm balance staff ronda: 2763 (13) balance staff ronda: 4581 (13) stem ronda: 1326 (13)
Other data: balance staff: U2217 stem: W2363 mainspring / battery: 1.20 x 10.0 x 0.08mm balance staff ronda: 2763 (13) balance staff ronda: 4581 (13) stem ronda: 1326 (13)
Family
Series 133 - 71
133: 18000 A/h
133.8: 21600 A/h
71: 21600 A/h, date
133.8: 21600 A/h
71: 21600 A/h, date
Related calibers
Zenith 133
Zenith 133.8
Zenith 71
Compatible Parts
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