Compass, Magnetic Direct Reading, US Navy Mark IX (for parts)
Here is core, for parts, of the WWII-era US Navy Aircraft Direct Reading Magnetic Compass Mark IX, as used in the seaplanes PBY Catalina and PBM Mariner Patrol Bombers.
The lamp compartment, compensating screws, and fluid are absent. The compass card is detached and ability to be salvaged is unknown.
Measures ~3.3 inches tall by ~5 inches wide and ~5 inches deep.