Extremely interesting big Longines Wittnauer deck watch / stop watch / pocket timer made for the US- military in the 1940ies. Metal chrome case, black dial with white 1/10th second indexes, 5 minutes register at "10". High grade Longines Wiittnauer caliber. Engraving on the back: "U.S.ARMY A.C. WATCH-NAVIGATION (GROUND SPEED) TYPE A-8 /AC263 SERIAL No. 41-92 Order No. W 535 AC 16036 SPECIFICATION NO. 27749-A MFR'S. ASSY:DWG.NO 29 Wittauner Watch and Co Inc. NY".
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