Quote Originally Posted by Robert Hall View Post
Where did you find them Jon?
They came with an 11x14 Studio Deardorff I puchased. Originally, my most recent research indicates they were used by the Naval Photography school at Pensacola, FL and were sold in the 1970's as surplus.

They may in be dry plate holders. I honestly don't know. They do have one dark slide in each holder and inside the holder is a dense foam. The "dense foam" material are fine and are not crumbling etc.