I'm trying to find a "scaffold" building device that is nothing but
an angled iron shelf that 'jams' on a pole and creates a shelf.
The contractors working on a neighbor's house used two of these
devices on two seperate 4x4(?) wood poles, and use a 10x2 plank
between them to build a "scaffold" or "walkway".

What are these things called. I search on scaffolding
and get, you guessed it, real scaffolding.

Thanks

Don't you just love answering you own questions?
Found it. It's called a 'pump jack'.
Thanks