Stadimeter Mark III in Leather Case, US Navy C-47 Judging from the consistent paper

Judging from the consistent paper stock and printing

which registers it on a dial marked in revolutions per minute

for dual engine aircraft of the US Army Air Corps during WWII

the USAF's first nuclear armed standoff missile) marked Confidential

Above that limit

Stadimeter Mark III in Leather Case, US Navy C-47 Judging from the consistent paperThis is an original WWII era Stadimeter Mark III as used aboard ships of the US Navy. A stadimeter is a rangefinder, used to determine the distance from the user to an observed known target. By viewing the target through the device and turning the knob until the presumed height of the known target is bracketed between the upper and lower limiters in the viewfinder, one can then read the distance of that target on the corresponding height on the side