Thanks everyone really. The "hole" I mentioned is more like a pin hole so it might have been sealed at one time. But it does look like someone made a hole with a small nail on the bottom.
I add another scan next to a ruler from a protractor and next to another item I have no clue on. I am getting a lot of things I do understand in the lots I am buying
but these are the things that can make you crazy. The item in question weighs 4 grams by the way with the wire attached.
And what could the tiny chains be for I wonder? If you know what the other item is by the way, feel free to let me know. Looks like a protractor itself. Seems complete
and is flat except for the handle
which is 90 degrees to the flat item so you can hold it in place. Real thin but stand up on a table.