American case?
Yes, Albert Wittnauer.
Information, contained in Longines' handwritten registers:
Originally, the serial number 5'51X'XXX identifies a wristwatch in stainless steel bearing the reference 4870 and order number 1597. It is fitted with a Longines manually wound mechanical movement, caliber 12.68Z and was invoiced on 23 November 1937 to the company Kohn, which was at that time the Longines agent in Prague.
Untouched, everything original, simply iconic.
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