Most of the viewers available for sale have a plastic viewer. This is one of the original, pre-patent Stori-views Co. Pixie Viewers. It is all cardboard and a rare find. Reverend Henry G. Kiehl submitted a patent application for this self-contained stereo viewer where the lens and diffuser apertures and the stereo view slot were all part of the bottom portion of the box making it double as a stereo container and viewer.
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