A rare WW1 period aircraft tachometer by AERA, Paris.
Circa - 1917.
In very nice original condition with clear dial, pointer & bevelled glass.
The mechanism freely turns but the pointer doesn't move.
As fitted to a variety of French aircraft / engines towards the end of WW1.
AERA produced fine aviation and automobile instruments of the period
and were equal to Jaeger in quality, identifiable by their unique 'Penguin' motif.