Puckerings has dated this piece to the 1910s.
Each ocular is twisted and pulled out to put into action, these are individually twisted to focus.

Complete with the original leather case. This pair was made for the English market and retailed by A. Franks Ltd. of Manchester.
Excellent condition. While folded and in their case they measure 3 1/4" x 2" x 1 1/4".
Item ID:37203
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Puckerings has dated this piece to the 1910s.
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