Simple idea.. what problem is it trying to solve though?
Only thing id be concerned with is the vertical movement on that rivet after a while that will work loose and you'll have a floppy brush head.
Not quite understanding the application.
The unique swivel joint mechanism is only held together by the rivet it will not get wear in the hole.
Will not loosen or flop around due to the way it sits on the swivel movement on the end handle.
Have used this just with the rivet in it without the locking cap on did not flop around.