Cyma Cymaflex 17 J Cal. Manufacturer Cyma. Signature ca. 1950: 337639, R.424, Cyma, Swiss, Tavannes Switzerland, 17 Jewels; Cymaflex-I. /Excl.crown, Thickness:4.1mm. 420KT: automatic, sweep second. 426KT: manual wind, sweep second.
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