I purchased this to go on top of the carpet in my office and it does work but it is thin. I would go for the next one up if I were to purchase one again.
Not wanting to damage the carpet pile under my rolling office chair I checked out Staples and found the 36" x 48" clear mat which is a perfect fit and my chair rolls easily on it.
I bought this product because of the majority of the reviews were great. A few did remark of how the mat gets indentations from the chair rolling on it. Which I am gaving problems with. Also the mat constantly moves. I am not happy with my purchase. Wish I could return it!