Puckerings has dated this piece to the 1930s.
The little catch releases the lenses from the case, they then spring open. They are very usable, with clear lenses and good magnification to help reading.

There is a silver bale, perfect for adding a silver chain or perhaps a silk ribbon.
Excellent condition, measuring 2 5/8" including bail x 7/8" wide while folded. Once open, the the two lenses span 3 1/2" wide.
Item ID:35975
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Puckerings has dated this piece to the 1930s.
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