Just to make it more legit, here’s a file for some keyhole hangers that I designed and included on this thread:
In a nutshell, I needed a way to hang some engravings and didn’t care to pound in/screw in traditional hardware. So, I made a stacked keyhole design. This is not a true keyhole in that the back is not engraved to create a slot for the head of whatever is sticking out of your wall. This is a two piece design with a larger slot in the back over a narrower slot in the front to mimic the material removal you would get out of a traditional keyhole design. It’s a trade-off to be a faster solution.
Here is what it looks like glued and installed:
And here is the SVG: