We purchased this mat for our office which had a 1 inch thick rug in it. Before we could not move the chair with someone sitting in it but now it moves perfect.
The desk chair which has 5 double rollers/wheels sinks into the pad and leaves indentations which the chair gets stuck in. My carpet is a firm berber. I will probably return the pad.
I bought this as a combo since I was buying a new computer chair and so far I love it. It provides protection on my floor carpet and makes the new chair easy to glide over. No rips tears permanent indentations etc. I have nothing but good things to say about it. We shall see how long this holds up as I have only had it for about a week.