It's been a while, but it kind of reminds me of the carrier for a DeJur Versaltile Professional enlarger.
thanks!
Definitely DeJur...I own one and have a sst of these for a bunch of different sized negatives. It’s a two-piece holder, which allows me to make enlargements from my dry plates since it accommodates the thickness of the glass (as opposed to a hinged holder.
Newly made large format dry plates available! Look:
https://www.pictoriographica.com
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