Help identify this tool

[Jal5]

all steel 3.5 " dimension full open jaws
Marked R62223.DET-1
Good patina of aged steel although it looks rusty in photo
Not a very strong tool more like a measuring device to me
Thx

[Papaw]

Adding your other picture from Cast Boolits . Shows that it doesn't close all the way. I have no clue on ID.

[Bill Houghton]

Seems like measuring would require a scale, or some way to lock the screw in position.  I  think some sort of specialized light duty clamp is more likely, but no idea for what.

[Jal5]

It came from my dad's workbench. He was a car guy but picked up tools from everyone. One guy he got tools from was a machinist and plumber.

[bill300d]

Wonder if it might have been for compressing a light duty coil spring of some sort.

[Jal5]

Compression tool for a spring but it would be a really small spring. Someone suggested a counterweight on a large scale?