Hamilton, early 4992B, United States Army Air Force Navigational Master Watch GCT, 22 jewels, adjusted six positions. 16 size. Circa 1952. Hack setting (stem pulls out to stop second hand). Military nomenclature on back. Case with signs of use.
These timepieces were used by the navigator and pilot as the airplane's master time source during World War II and thereafter (this example dates from W.W. II). It was intended to be set to Greenwich Civil Time (GCT). This unit is supplied with the seldom found original metal carrying case, also with full military markings, designed to isolate the watch from magnetic fields and aircraft vibrations. The carrying case is in good condition. A very nice example of a Korean War era Navigational Master Watch GCT.
U.S. ARMY A.F. GEO. H. ADAMSON TECUMSEH, MICHIGAN, U.S.A.