Aircraft Clock, 8-day, Type A-11 PN 21AE For parts or repair

This is a mechanical WWII-era aircraft clock, Type 11 Bulova PN 21AE, that was used across nearly all aircraft of the US Air Corps and Air Force, including bombers B-17, B-24, B-25, and fighters P-38, P-40, P-47, and P-51. 

The time is set by pulling out and rotating the knob at the front corner and rotating.  The clock winds but does not run. Measures ~2.25 square and ~1.25 inches deep.