A World War II Hamilton Watch Co. pocket watch in USA 'Navigational Case', open black face, named 22 jewel movement, Diameter 5.1 cm. The back cover engraved 'AN 5740 MFR'S PART NO. 4992B ... HAMILTON WATCH CO.', the spring gimballed grey painted steel case with maker's details to plaque, pivoting circular inspection plate. Diameter 10 cm.