The caliber UMF 24 from the VEB Uhrenkombinat Ruhla (UMF = Uhren- und Maschinenfabrik = watch and machinery factory) is probably the best-known mechanical movement built in the former GDR. Around 130 million of these simple and inexpensive pin lever movements are said to have been built between 1963 and 1990, many of them for export.
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