I have an awkward installation here. The brand is Neptune, out of Canada. The shower arm has a fitting with rubber O-Ring that set screws on the ten pound heavy shower arm and head. It's supposed to use two screws into the solid surface. Expecting large tile to drill into, what I found was rocks mortared onto the wall. Has anyone else drilled into rocks to secure a wall bracket like this?
Rocks mortared onto the wall.
This takes a wall plate. The plate needs to be sealed to the wall. These are the rocks that need to be drilled for anchors too.