UNIS-FRANCE - 76-3 (c.1930)
The body has an opening where the stereo glass or paper photo is inserted for viewing. The binocular eyepiece is focussed by a knob on the right. Their interocular distance is fixed.
On the top of the body, a reflector is used to capture the light and project it inside the body when viewing paper photos.
On the back side, a door supporting a glass can be open downwards to permit viewing of glass stereo plates by transmitted light.