Elgin Military USN Pilots WWII c.1942
Ref.FSSC 88-W-800 Screw Down Case Back Made in USA 

Most likely this watch would have in the Pacific theatre during WW2 as most USN pilots were deployed there.
The FSSC 88-W-800 spec watches were produced for US Navy pilots and were essentially made to the same specification as the USAAF Type A-11 watches, except the  88-W-800 required a luminous handset and dial. All 88-W-800, like their Type A-11 siblings, had sweep second hands. Movement is a Caliber 685 with 15 jewels 
Cosmetically overall in great condition and running well