This is my 3rd of the same chair mat. But this time Staples had none in store so we [the sales guy and I] ordered it right there at the store. What arrived was a mat w/NO teeth.....well baby teeth....it slides all over the place on my carpet. I have to pull it back into place at least 4x a week. Too bad cause this HAD been my favorite mat and my fav place to buy the mat! Unless the sales guy ordered the wrong mat for me [the whole plus side of the older version WAS it's big teeth and strong/thick base] this present mat has NO grip and isn't made has hardy as all the others!
I had two office mats that had turned yellow after nearly 8 years so I found this mat and bought two. They are the same size as my previous mats so they fit perfectly. However they have a smoother surface than my older ones which I really enjoy; less noise when the wheels of my office chair(s) swivel around. Speaking of which these are good for light to medium weight office chairs; in general these mats will start to get indentations on ANY carpeted floor if your chair is a heavyweight (it'll sink into the same spot over time). Plan ahead if you have carpeting and don't get a really heavy chair. Also the lip of these mats is NOT beveled to keep the chair on but sloped to let the chair slide off; this may be good or bad depending on your preferences.