Manifold Pressure Gauge Set, Dual Engine, for 4 Engine Aircraft, Bendix, Constellation F-86 The right hand knob turned

The right hand knob turned the system on and off

so it is pre March 1942 vintage

The subsequent Kollsman model 716K-02

It was for aircraft with shallow/slow climb/descent speed i

Manifold Pressure Gauge Set, Dual Engine, for 4 Engine Aircraft, Bendix, Constellation F-86 The right hand knob turnedThis is a pair of 1950's era dual engine Manifold Pressure Indicators, made by Bendix and labeled for engines #1 & #2 and 3 & #4. Used in post WWII 4 engine aircraft such as B 50, C 54, C 121 etc. The 1958 Flight Manual of the Lockheed C 121 Constellation shows these instruments located on the pilots instrument panel as well the flight engineer's panel. The instruments are in very nice condition for their age. The dial markings are clear and the glass