I have this encased stamp and I haven't been able to find much information on it. I've seen a few for sale at some auction houses but they are basically 'here it is, buy it if you want' with no actual info about them.
For example, there's this one https://(Offsite URL shortening not allowed) /35JFNC.
Does anyone know the history about them?
When they're from? Why they exist?

