Airspeed Indicator, 700MPH, Army Type F-2, US Army Air Corps, WWII Fairey Fulmar the manual describes the instrument's

the manual describes the instrument's use

Representatives from several aviation training commands conducted extensive tests with an instrument of this sort in September 1943 and recommended that it be 'considered for adoption as the standard sextant for the Army Air Forces'

Measures ~3 inches by ~3

The metal seal is in place in the lower right of the case

By seeking a signal from a ground transmitter

Airspeed Indicator, 700MPH, Army Type F-2, US Army Air Corps, WWII Fairey Fulmar the manual describes the instrument'sThe Army Type F 2 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 2 was made by Bendix, part number 1426 37A A6, and has a