Zenith 50.5

Basic Information

NameZenith 50.5
Alternative NameETA-ESA 9164
Base CalibreETA-ESA 9164
ManufacturerZenith
Launch Year1969
Caliber FamilyDescription
50.0: date
50.5: day, date

Related calibers
Zenith 50.0, Zenith 50.5
Is COSC certifiedNo

Technical Details

Lignes Dimensions13 ‴
Dimensions29.4 mm
Height5.55 mm
Further MeasuresMounting Diameter (Dm): 29.0mm
Stem height (T): 2.6mm
Mounting Height (F): 2.0mm
Power Reserve(not set)
Frequency300 vph
Jewels12

Complications and Specifications

ShapeRound
Complications
  • Sweep Second
  • Day
  • Date
  • Chronograph Stopwatch
Regulator TypePinned Regulator (or Index Regulator)
Movement TypeElectromechanical
Escapement TypeSwiss Lever
Control TypeTuning Fork
Winding TypeStem Winding (Crown)
Setting TypeStem Set (Crown Pull)

Additional Information

Hand Sizes1.50 x 0.90 x 0.25mm
Hand Count3
Country Of ManufactureSwitzerland
NotesRemarks: 1969-
Other data: stem: ESA 9162 mainspring / battery: 343 (original, mercury), 344 (replacement, silver odixe)
Signature1970: 7058237, ESA 9164, 22, 22 Y2, Eterna Sonic 1551, Lic. Bulova & Pat. ESA Swiss, 12 Jewels (Eterna 1551, ETA-ESA 9164)
Import Codes

Metadata

Created AtSep 15, 2023
Updated AtMay 26, 2026, 4:43:57 AM
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