Swiss platinum split second chronograph watch Circa 1923

Platinum open faced split chronograph watch 
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An elegant, ultra flat Genèva pocket watch with minute repeater and split seconds chronograph, circa 1923.
A platinum case, silver dial, 30 min. counter, bridge movement, very finely ground, bevelled double hand tong with separate ratchet wheel for split seconds chronograph, two hammers / two gongs, gold screw compensation balance
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Diameter: 46 mm
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Weight: 65 g
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Signed:  Audemars Piguet & Co.  Swiss