The gauge plastic slips forward with chair movement forward and back to the point where it hits the Base of the desk unit and curves upward. Did try a piece with tentacles that grip carpet but gauge of plastic was too thin and constantly took impressions from the chair legs. Adequate.
The mat is okay; however I wish I had spent a few dollars more and purchased a heaver mat. Had trouble with chair moving on carpet this one did not help much. The match is too thin and had indentions under the wheel after sitting in the chair I weigh 163 - wonder what it would do with a person weighing more. Can get by with it but not satisfied with my selection. -jwr