Oxygen Flow "Blinker" Indicator, PN 1506523 AN-6029-1 C-46 Would have been used in

Would have been used in ground installations (as opposed to use within aircraft

We have not identified what aircraft may have used the tachometer

Battleship Iowa

The Altitude Selector Switch allowed the pilot to set the lower altitude limit over the terrain

which would have the ground map of the terrain below

Oxygen Flow "Blinker" Indicator, PN 1506523 AN-6029-1 C-46 Would have been used inThis is a WWII era Oxygen Flow Indicator "Blinker" made by Delco PN 1506523. This indicator was used across nearly all aircraft of the US Army Air Force and US Navy. When the oxygen system was switched on the oxygen flow caused the center 'eyeball' to open and close, or blink, thereby confirming to the crewman that the oxygen supply was indeed flowing. This indicator is in exceptional condition for its age. The glass and case are intact and clean.