We needed to have a chair mat that would protect our newly laid laminate floor in our study from our desk chair with wheels. It was just the right size and the chair rolls smoothly over it and no worries about our new floor. It is specifically for a floor rather than carpet and I'd definitely recommend it.
It's my mistake I'm sure but I have fairly new carpet and was new to purchasing this and didn't know what I needed but now I realize I needed something meant for thicker carpeting it slides around a bit underneath me so I have to reposition it every other day or so and my chair barely moves across it. It's my fault I should have bought something more pricey that would be better for the thicker carpet I just didn't know.