Seen these before .. Just can't remember what they are.

[creskol]

I know I have seen these before, but my memory fails me. Made out of steel and is 1.5 inches in diameter by 1/8 inch thick.

 

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[TomPA]

A flat "pocket wrench" for removing a bolt/nut? Just a guess that might remind you of what it was!

 

[nhbenz]

A lot like automotive wheel alignment cam washers... but maybe just used the same way, as I think of those as being a bit thicker than 1/8”.

 

[A2coins]

hmmmm

 

[Reanm8er]

Skate key?

 

[Rookster]

I think definitely maybe one of the above