Could not find anyone to help. There were only two types of office mats that we saw to go on carpet and they were all the same size. I think one was for carpet the other for hardwood or tile floors. Kind of a frustrating experience.
This Carpet Chair Mat has been under our desk chair for a year. The mat moves around on my 1987 medium pile carpet. However it provides carpet protection & allows chair to move around without the mat being depressed--which is good.
I put the mat down and put my office chair on it and have been sitting in the chair and wheeling it around for about 4 days now and so far it's working fine. The mat is softer than some but so far that isn't interfering with my use. For the price I'm very satisfied.