The chair mat indents from the chair feet or rollers creating these holes the stay in the mat and keep you from rolling around the mat. You actually have to pick up the chair to move out of the divots in the mat. Everytime you change positions of the chair new divots are created and they remain. This is very problematic and aggravating.
It is fine but I rated it a 4 because the sticker that held the paperwork I still can't get all of it off and it is really aggravating. And I don't know why I have to put a title in - your asked for the review of this product so I would think that could just auto-fill.