Seiko 6138, 6139, Transmission wheel, no: 505613

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  NOS SEIKO original part in factory sealed packaging.

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  Seiko part number: 505613

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  Fits: 6138 A/B, 6139 A/B

Technical data: SEIKO 6138A

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  21 jewels, automatic wind, chronograph, 60 s, 30 min, 12 h counter, day-date.
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  S: = 27.0 mm.
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  H: = 8.0 mm.
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  N: = 21.600 A/h.
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  Power reserve: 45 h.

Versions:

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  6138A:
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  6138B: modified switch mechanism.
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  6139A: without 12 h counter.
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  6139B: without 12 h counter, modified switch mechanism.