Esan Stereo Viewer

Italy, 1950s

This is a rare, mid-century Italian stereoscope that uses two 35mm filmstrips that are advanced vertically through the viewer. There's a red knob on one side and a white knob on the other side, both are attached to the same spindle that uses sprockets to advance both strips simultaneously. Each filmstrip has color along the edge, either red or white, so you know which side of the viewer it goes in. Someone got really creative on this one.