A torus with its hole size equal to the thickness of its ring is split
"longitudinally" with a cut the makes a 360 degree twist during its travel
around the torroidal ring.
The twisted cut separates the torus into two equal but interlocked parts:
These interlocking parts can be rearranged so that the outside of one
touches the inside of the other to make a very pleasing configuration:
In fabrication: "