Nah, its different from that.
In the above pics, in the bottom left pic you can see a rounded half moon shape.
Thats where the disc is, inside the unit theres two thin flat metal plates that contact on each side of the silvery disc.
I did find a pic of the actual disc. The ones I have seen don't have the thin mica disc connected to it
I just figured it was a diode of some sort & didn't bother saving them.
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