A friend of mine showed me something he found. It looks somewhat industrial, but nobody can figure it out:
A ring, about an inch and a half in diameter, about a centimeter high. It was made of nine circles, one cm. in diameter around the outside.
The whole thing was made of metal, in two pieces, welded together to join the half-circles.
I know the description is vague, but does anyone know what this thing is?
Thanks in advance