Answer:
It is weightless, you can see it. If you put it in a barrel it will make it lighter?
who do you think you know but sometimes you don't
Gets rid of bad ones, short and tall. Tightens when used, one size fits all.
I go around in circles, but always straight ahead. Never complain, no matter where I am led.
A nut cracker up in a tree.
What covers its face with its hands, speaks no language, yet most known what it's saying?