Airspeed Indicator, Sensitive, 700MPH, Army Type F-1, US Army Air Force, WWII Cessna such as fighter ME 110

such as fighter ME 110 and bombers JU 88

loosen clamp (C)

The small protrusion right of the digit display counter was likely used to reset the counter to zero once pressed

This is a Machmeter

The knob turns and the display rotates as it should

Airspeed Indicator, Sensitive, 700MPH, Army Type F-1, US Army Air Force, WWII Cessna such as fighter ME 110The Army Type F 1 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 1 was made by Bendix, part number 739U 03, and has a serial