Photos provided by Andy Mason, UK, digitally processed and grouped by Jock Dempsey.
A squaring stake is used to dress bent corners and have reliefs on the sides of the working surfaces. This one will reach inside hollow work and has both round and square ends. Common squaring stakes are mounted directly atop a shank.

Note the curious hole at the middle of the stake. This is a hand forged, probably wrought tool with hardened steel work faces.