20Q: Round 5

I'll skip next time it's my turn.

Don't, please, you had pretty much give us some useful clues. :D

Wth is similar to nanotube? :confused: I haven't make my guess yet, but it's about my turn. Is it pen ring? This thing in the middle:

If you put him at the bottom of the list now, and then put me on the bottom of the list, it corrects the problem.