What is this ? A “Minute clamp” ?

[Vern P]

I picked this up. In the back of my "poor mind" I have seen this, but don't remember where.   Is this part of the "Minute Clamp" I have asked about before ?
Who knows what it is ? Have one ? PLEASE share what you know or have.

[FABphones]

...Is this part of the "Minute Clamp" I have asked about before ?

Thread here:
http://www.classicrotaryphones.com/forum/index.php?topic=25663