The size/shape of the mat is fine but it does not stay in place. Just one seating and when I get up the mat has moved in one direction at least an inch and is crawling up the file cabinet that is under the desk and the end support side. of the desk. I went back to Staples to ask for any suggestions about how I might keep the mat in place. The sales person was unaware of the problem and was clueless how to solve it. There doesn't seem to be a rectangular mat of a suitable size to try as an alternative.
We have an "L" shaped desk that is sized in such a way that available rectangular mats we looked at were either too small or too large. This one fits perfectly! On the downside the mat does shift a few inches over time as the chair wheels roll back and fourth. This was never an issue with our old mat that used sharp 'spikes' at the bottom instead of this one's current design. Overall though I am satisfied and would buy again.