Bulova A-11 military watch - "The watch that won the war".   Just before WW2 the US Air Force developed the "A-11" standard for a modern military navigation watch. Bulova was one of three American manufacturers commissioned to produce the watch.   The specs prescribed a hacking feature (second hand stops completely upon pulling out the crown) for ease of synchronization, When the briefing officer said "hack" the crewmembers would simultaneously push the crowns on their watches so they were all synchronized to the second.  The 10 AKCHS movement is produced in 1943 as indicated by by the Bulova date code "X" next to the Bulova sign.  The case is chromium-plated brass as stainless steel was reserved for other to wartime use. The back is stainless steel and displays a.o. the serial number including AF (Air Force) and the issue year 1943. The watch measures only 32 mm across (not including the crown) but has a big history, likely to have experienced actual war time action (unlike the 1945 dirty dozen ;) ).  Please study the pictures; the case shows some wear. The watch is sold without the strap. .