The mat is terribe. We purchased the more expensive model because others have failed and this one is no better. We have only used it for a month and it is already cracked and broken.
Absolutely awful quality. Starting to show permanent indents after literally one day of use. And they won't accept a return now because it isn't original quality. If you want to NOT be able to roll your chair around due to instant permanent indents, this is the model for you.
I calculated which mat to buy based on the 'How To' measure the carpet thickness, and that did not work. This mat is better than no mat, but it is not firm enough/ thick enough; the chair leaves dents, and the rug is soft, so getting rolling again is tough. I needed a thicker/stiffer mat.