Zeiss Ikon Steritar is a stereo attachment (beam splitter) allowing to take stereo picture pairs.
This adapter allows using Steritar attachment on lenses with M46x0.75 filter thread.
Make sure that your Steritar has M34x1 male thread since I've heard that other version exists (with larger thread diameter).
The adapter consists of body (made of anodized aluminium) and bronze insert secured by means of 3 sec screws. Such design allows angular adjustment and alignment of the attachment on any particular lens.
For sale is the adapter only.
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