I bought a pipe clamp and after it arrived I found it does not tightly fit the pipe because I think it is supposed to be used with a grommet.
The problem is that to find a grommet to fit this thing, I need to know what it is called. What is the name of the item I need here?
(Note that it is NOT an electrical grommet. Electrical grommets that fit into a hole in sheet metal are totally different.)