This item was not what I expected. It says it was made for high pile carpet but it's not sturdy enough for that kind of carpet. The chair rollers just sink into the plastic leaving divots. Would not recommend purchasing especially at this price.
Weight of user and chair on medium pile carpet causes temporary depressions to form. Maybe that would have been prevented if the mat were thicker? It doesn't move around at all though.
I bought this mat because everything else was out of stock. It is thin and the chair legs are almost going through it with only having it for about a month. I definitely would buy something else.