Has anyone seen an old style perforation with 2 slits on each side of the postage stamp?

The perforation is two small rectangles on each side of a George Washington 2cent stamp. I have two stsmps with these perforations curios about them.
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The perforation is two small rectangles on each side of a George Washington 2cent stamp. I have two stsmps with these perforations curios about them.
Answers
(checks notes) - uh, this is a coin collecting forum.
10-4,
My Instagram picturesErik
My registry sets
They are probably privately-perforated US stamps that were originally issued without any perforations.
The purpose was for them to work in early vending machines and/or automated affixing machines.
Some varieties can have collector value. If you can post a picture I can tell you.
This.
Quite common on Washington-Franklin issues. The Shermack's had some value but are too easily faked.