This is a Bulova A11 Gents Military Hack Watch. This is official designated Ordnance as per the markings on the back of the case. 
 
The A11 was a collaboration between Bulova, Waltham & Elgin, people called the A11 'the watch that won the war !' This is a very good example of this watch.
 
The case and dial are in very good condition, not perfect by any means but for its age and it's history, it's been well looked after. 
Inside the case is a Bulova is 17 Jewel Movement marked Bulova Watch Co.USA, the hack function works as does the movement. 
 
Cosmetically overall this is very good condition and running well