This harmonica adapter that allows users with dexterity problems such as quadriplegics to use a harmonica without having to worry about dropping it. it also allows the use of one hand. The adapter slides on whatever side you see fit. simply slide your thumb in the ring and you're good to go.
There are two versions:
1.ring that is able to rotate 360°
2.static ring that is angled at 20 degrees
It should work well on most standard harmonicas. I have tested on my Hohner Big River harmonica, Hohner Blues Band and East top harmonica.