Mystery graduated size tool set

I just added a photo of the un-related found lever part (the notches and boss fit nearly perfectly) to answer an earlier comment.
I don't know if this is missing parts of a kit. If so then this tool is possibly useful to twist to break out chair rungs for re-gluing, or some kind of plumbing gripper?
I have found an unrelated lever that nicely fits all 3 sizes and hooks under the bail and compresses the clamp to grip a cylinder while allowing strong rotation of the assembly.