Roger Long wrote:
You would probably enjoy making your own mobius strip. Much cheaper and
easier to understand. You'll usually get a light going on expression when
you trace around it and show someone that it only has one surface.

--
Roger Long

When I was 13, I was obsessed with Mobius strips in every fashion, I
made them from paper, plastic. soldered metal, etc. I tried to make a
Klein Bottle without the "junction" by joining the edge(s) of a mobius
strip with strips and fastening them together, tried to make part of a
Projective Plane, etc. My kids do not share this obsession.