Quick question - what is this for?

[Deb Mac]

Got my see snake behind that wall (not enough room to reach in and feel). The bottom screw is another toggle bolt, the top has nothing…
Back inside and though I can get that top screw to turn - it is an Allan screw and I managed to force a key into it and get it to turn. However, since it isn’t holding anything in place it’s academic. It’s the epoxy holding that little goodie to the wall. And that isn’t coming off without doing a number on the wall. So it stays where it is. Maybe I’ll find a use for it some day!