I’m sure I have the cover somewhere but it was useless for me because I only put the Ollin BTX adapter on when I wanted to film/snap pictures and took it off when actions complete.
*update* On second thought. That cap is for single monocular spotters (not BTX with two eye lenses).
They show that it’s included but that wouldn’t make sense to include one cover when the other eye lens is open. Misleading pictures from Olin and again wouldn’t make sense with double lenses.