Helvetia 830 (11.5'''), Winding stem, Ronda: 963

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  Manufacturer Ronda no: 963

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  Thread: 90

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  Fits cal: 830, 837, 838, 844, 845 (11.5''').

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  A: = 64
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  E: = 418
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  B: = 88
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  C: = 125
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  D: = 90
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  F: = 50

Data Helvetia 830

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  17/21 jewels, manual wind, sweep second.
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  S: = 11.5''' 25.60 mm.
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  H: = 4.30 mm.
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  N: = 18.000 A/h.
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  Power reserve: 44 h.
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  Mainspring: 1.40 x 10 - 0.12 - 310

Versions:

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  830: manual wind.
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  837: automatic wind.
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  838: automatic wind, redesigned.
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  844: automatic wind, date.
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  845: automatic wind.