atcomsystems.ca/forum Forums General General Telephone & Systems Information Finish nuts for through-wall threaded rod?

I guess you could call it a weld. They don't strike me as being made of the same material. The threaded stud shows some rust, while the mushroom cap seems more like stainless. I could take some more photos when I go to work tonight. It's definitely not removable, the thread and cap are permanently joined by what looks like a weld.