Airspeed Indicator, Sensitive, 700MPH, Army Type F-1A, US Army Air Corps, WWII
The Army Type F-1A Airspeed Indicator was used across a number of US Army Air Corps and Air Force aircraft during WWII, including heavy bombers B-17, B-24, B-29, medium bombers B-25 and B-26, as well as light bomber A-20, according to the Accessories Interchangeability Chart dated Feb 1945. It was also used in versions of US Army Air Force WWII fighters P-38, P-39, P-40, P-47, and P-51. This F-1A was made by Kollsman, part number 739U-03, and has a serial number prefix of AF44, indicative of a 1944 manufacturing date. On its face is embossed AC US ARMY.
According to the spec sheet in the Index of Army Aeronautical equipment Volume 6 Instruments, dated 1944, the Army type F-1 is a sensitive airspeed indicator. The pointer makes one revolution every hundred miles per hour. A smaller inner dial indicates hundreds of miles per hour.
It is in good condition given its age. The dial and glass are intact. The old seal around the glass is peaking out at ~3:00 o'clock, see photo.