Product review (1 stars): Didn't work for me.
It was very easy to install.  However, it still hasn't un-folded enough to seal, especially at the bottom.  I used near-boiling water, then cold water to loosen it up.  After installation, I used a heat gun.  I wish I hadn't spent the money as I still have a big, white, useless "box" using up space in my basement.  :(