it can be used t drill a hole in the center of any 1/2" round but tis was what I made it for.
Finding clevis pin the length and size I wanted might not have been difficult, finding a hardened one though?
To make them I wanted a drill jig so I wouldn't have to fiddle around trying to stay on center of something round plus I wanted consistency in the hole location.
What I used was a salvaged cemented carbide tool shank 3/4" sq. these make lots of really good second life tools.
I bored a hole through the length of it then cross drilled for the cotter pin location in the clevis pins.