What is this long screw in my Blue Angel?

[lusn]

I picked up a Blue Angel recently. I am curious what this long screw is that protudes out the bottom of the chassis...

From the outside...

 

[Don]

It tensions the chassis so that is won't rattle and improves the chassis' connection to the shielding in the cabinet.

 

[MusicManJP6]

It tensions the chassis so that is won't rattle and improves the chassis' connection to the shielding in the cabinet.

Correct! (ding ding ding ding!!)