What is this bracket or tool made from steel bar?
It's a single support for a staging plank.
It would require at least one more like it (plus a plank to run between them) to be useful.
The angled slots suggest specifically for holding a toe board (keeps workers from sliding off the edge) at the edge of roofing work, since that allows the support to be shingled over and removed without direct access to the nails holding it in place, but it's not (what I would call) a &quot;Roof Jack&quot; with a similar holding arrangement and a board support that can be adjusted to be level or near level on the slope.

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