One more try before I give up
It's not switching fingers, it's falling off his finger because the hinge is open on the back.
Again; Do you see a similarity in the shape of the C shaped ring (with a flat front and a hinge at the back) here?
One can use one microphone, two, even three or nine. They might have different functions. The big one he uses is to talk to the crowd, the small one might be recording. The event is probably being filmed and that small microphone is recording the sound for that.
Ok buddy.