This particular mat was delivered in a timely manner on a cold winter day in a heavy cardboard "tube" which turned out to be a big mistake. The plastic material had "taken on a set" and wouldn't uncoil (unroll) and warming up in the house had no effect on the stubborn plastic which reminded me of some kind of cheap recycled hard pop bottle junk material. Why the mat is not kept in a flat storage position is beyond reason because it had become unusable in the coiled position and nothing on "God's green earth" was going to change that so I returned it to the local Glenview Ill store. The management was very understanding and I received a full refund. I was told that it was a "closeout" and it wouldn't do any good to reorder it.
Waiting till it completely flattens....right now it's got a "hump" in the middle and I would have thought the heat in the house would have flattened it by now.