A very disappointing purchase. I noticed right away  the rug was unusually light for its size. 
I had ordered the thickest one available, which was only a medium,  0.5  to 1.0 in.  The rug was nowhere as thick, never exceeding 3/8 in.,  and it was flabby, totally lacking firmness, curling at the corners, and causing us to trip every time we walk across it. After almost a week now, no sign of it settling down flat.
I am so angry I can't even be bothered sending it back.  A waste of time and money, even for a lower-priced item.