I bought these mats a long time back. Nice to base on them, as they are not as tough as your floor.
No chip or injure things-- not so old-- I just rolled them up, and that is why the pictures reveal a fold.
I expect if you leave it down, the fold will certainly go away.
This one is 20" X 36".
I have TWO of these mats-- If you want both of them, that would be $100.00.