Answer:
The one who makes it, sells it. The one who buys it, never uses it. The one that uses it never knows that he’s using it.
What goes through a door but never goes in. And never comes out?
What word starts with 'E', ends with 'E', but only has one letter? It is not the letter 'E'.
I have a hundred legs, but cannot stand. I have a long neck, but no head. I cannot see. I'm neat and tidy as can be.
What is never used unless it's in a tight place?
I start with T end with T and within me is T.