On Apr 23, 8:57 pm, dpb wrote:
On Apr 23, 3:35 pm, wrote:

(For 1/2" 3/4" etc)

I see two types:
One type fits around the pipe and uses two screws fastened into the
wood (or whatever)

The other has a round copper piece where a large wood screw goes
through the middle and then two pieces with two copper screws hold the
pipe in place.

The first type seems much easier and cheaper but there must be a
reason or specific application for the second type. Anyone know where
to use the second type?

1) Where there's possible need to remove the pipe w/o removing the
clamp mount.
2) Whereever one wants...

Why would anyone "possibly need to remove a pipe" ? If you have to
remove a pipe then the minor holes in the sheetrock are the least of
your problems. Secondly, couldn't you pretty easily remove a pipe
without removing the clamp mount regardless of which type you use?
ie: loosen the screws a little, cut your pipe and pull it through.
Sorry, your post made very little sense.