Make two tubes, on the same axis. (don't cap ends)
Say we make them along z axis (Make tube at front view).
One tube size to x=0.8, y=0.8, z=5
One tube size to x=0.6, y=0.6, z=5
Move both to 0/0/0
Take the inner tube, and flip normals
Mark both tubes and merge them.
Create new surfaces at the edge of both tubes
Voila - ready...
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