Product review (1 stars): Better options available
I purchased this duct kit last week.  As I expanded the duct, very gently, it completely ripped apart into a spiral when it was only about 3-4 feet long.  It is too fragile to expand, and there is no way you could expand it to the full 8 feet length that is in the description.  I purchased another semi-rigid duct at the store so that I could feel before purchasing to make sure it was going to be sturdy enough to expand without breaking.  It is the GE Universal Gas and Electric Dryer Duct Kit, and it works fine.  I was able to expand it with no problems, and it costs around the same.