The only issue I have with this chair mat is that the bottom side that touches the floor isn't smooth enough to create the proper "suction". It is not as bumpy as the top, but still bumpy enough to allow it to slip sometimes when stepping on or off of it. This doesn't cause a safety issue, it is not that extreme. It just gets out of alignment and has to be shifted back into place more often that I would like. I bought this mat to go next to another existing one and the specs and measurements provided in the description made it easy to find the right match.