Certina 13-20-180/1, Barrel with arbor

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  CERTINA original parts in very good used condition.

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  Comes without mainspring.

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  Fits cal: 13-20, 13-21

Versions:

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  13-20: N: = 19.800, no mountings.
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  13-21: N: = 19.800, mounting threads.
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  13-22: N: = 21.600, mounting threads.