What is of interest about this watch is that it has the same 15.26 movement* as one of the Longines Tartarugone 1935 of the Czech Air Force.

Longines Large SS 38mm Rare Model, "Serbian Army Corps", ca.1939
http://www.oldwatch.club.tw/Codetail...ng=Eng&Model=1

A Military Longines Marked With the Coat of Arms of a Long-Gone, Eastern European Monarchy
http://hoodinkee-beta.squarespace.co...-a-long-g.html

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* Longines began production using their common 5.65 mm Cal. 15.94 but switched to the thinner 4.5 mm Cal. 15.26 for a second series. This movement was not produced in much volume due to the Great Depression and was perhaps too fine for a military timepiece with its gold-plated bridges. Once the Czech military specifications were in, Longines switched to the cheaper Cal. 15.68, and this is the movement found in most military-issue Longines “Tartarugone” watches.

IN-DEPTH: The Lineage of the Longines Czech Aviator Chronometre
http://luke-rottman-8vjd.squarespace...w2vuh65lw3k4k1