Whats it called?

[plowjockey]

"C" shaped pieces of slotted steel, with oval slots cut into it (usually), cut to length, as needed.

Used in conjunction with threaded fittings, threaded rod, nuts, etc, to mount switches, fixtures, furnaces, pipes, conduits, etc., to walls, ceilings, floors, in indstrial installations.

Nearly everything.

The plumber I work for inadvertently( I think), called it "dexion", but all I can find, for that is industrial shelving..

This material is used to just mount stuff.

[CIW]

Are you thinking of uni-strut?

[plowjockey]

That's it.

Thanks

[rancher1913]

sometimes also called "kindorf" but unistrut is the most common name. most electrical supply stores have it.