Radio Control Box BC-450A for SCR-274 Airborne Radio Set US Army it make sense that this

it make sense that this may have been specified for helicopters

It displays airspeed up to 700 KPH

We have observed this ASI in photos of the instrument panel of the Curtiss Jenny biplane and the post WWI Martin MB-2 Bomber

If you have a Drift Sight Head in your collection

Radio Control Box BC-450A for SCR-274 Airborne Radio Set US Army it make sense that thisHere is an authentic WWII era Radio Control Box BC 450A was a component of the SCR 274 N command radio set as used in aircraft of the US Army Air Force and US Navy such as heavy bombers B 17, B 24, and B 29 and medium bombers B 25 and B 26. SCR 274 was a multi channel, multi component aircraft radio receiving and transmitting system (see 2 page description in photo gallery). The BC 450 provided the pilot with remote control of 3 radio receivers. This