Airspeed / Machspeed Indicator Kollsman A3422310002 RAAF but the outdated cord has

but the outdated cord has been removed for safety

The instrument looks terrific and would make a wonderful display piece

but may be operated mechanically by turning the key

The telescope was positioned within the bore of the gun during the sighting procedure

which would be displayed on the ALT gauge

Airspeed / Machspeed Indicator Kollsman A3422310002 RAAF but the outdated cord hasHere is a combination Airspeed Machspeed Indicator, 0 400 Knots, made by Kollsman. The mach number is adjusted for the aircraft with a hex key turning the blue screw on the rear case. Likely from the 1960s or 70s and a US Navy aircraft. Measures 3. 25 inches diameter and 4. 25 inches deep.