Altimeter, Civilian Cessna Czech oat can be operated in

oat can be operated in any part of the aircraft where local magnetic disturbances caused by engines

By rotating this lens to align North with the compass pointer below

The rigid shell with reinforcing ridges

according to the US Air Service Command's Airborne Radio Equipment Handbook dated 1943

Altimeter, Civilian Cessna Czech oat can be operated inThis is a civilian altimeter marked for use in a Cessna aircraft. It is date stamped November 1959. The knob is used to adjust the altimeter to the barometric pressure is displayed in the small window at the 3 o'clock position. The glass and case are intact, and the knob rotates, and the pointers move. Measures 3. 25 inches diameter and ~4 inches deep.