Vintage Rare Fuji Fujinon Compass Illuminator 7x50FMTRC-SX Binocular Part Japan

Fujinon Compass Illuminator for the Fujinon 7x50 FMTRC-SX Polaris Binoculars. To solve this problem, the illuminator is a slip fit device, attaching onto the compass of the binoculars.

Not sure if used before but installed new battery due to age.