Suction Gage, AN 5771-5, US Army Air Force WWII Luftwaffe The counter-drum-pointer altimeter consists of

The counter-drum-pointer altimeter consists of a pressure altimeter combined with an powered servo mechanism

VBC (Vertical)

while the index mark was not labeled on this version) and the C-2 is ~1 inch shorter

made by Elgin to Air Corps US Army spec #94-27749

Suction Gage, AN 5771-5, US Army Air Force WWII Luftwaffe The counter-drum-pointer altimeter consists ofThis is a fine example of an WWII era Suction Gage, AN 5771 5, made by US Gauge, part number AW 1 7 8 21 AK. This indicator has a serial number prefix "AF 43", evidence of a manufacturing year 1943. The AN 5771 5 Suction Gage was used across all aircraft of the US Army Air Corps, including bombers B 17, B 24, B 25, fighters P 38, P 40, P 47, P 51, and transport C 47. The Suction Gage measured the amount of vacuum generated to power the pneumatically