Certina 13-20-724, Balance, complete

• 
  CERTINA original balance in very good used condition.

• 
  Fits cal: 13-20, 13-21 (19.800 A/h)

Data:

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  17 jewels, manual wind.
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  Size: 5,75 x 6,75´´ 13 x 15,25 mm.
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  H: = 3,55 mm.
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  N: = 19.800 A/h.
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  Power reserve: 43 h.
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  Mainspring: 1.35 x 5.5 - 0.065 - 210

Versions:

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