This Staples Model #: STP-17436 which was in stock at my local store and was supposed to work with an 1/8" flat pile rug but was too thin and chair would not roll. Returned and purchased model 20229-CC designed for a 3/8" flat pile rug which works just fine. I have three of these.
First it was difficult to unfold and place where it was needed. Second it is difficult to roll my chair (or any chair for that matter as I tried 3 different chairs) on it to get a comfortable seat in front of my desk. I hate this product!
I've ordered these over the last 10 yrs for use on low pile commercial carpet. Here's the thing these are cheap but crack in 1-2 yrs depending on the users' weight. But since $130 mats crack in 2-3 yrs as well at $30-$40 each these still offer the best value prop. Average lifespan I've seen is about one year is you weigh 200lbs (like me) and 2-3 yrs if you weigh 125-150lbs. If anyone experiences a 5 yr life on more expensive Quill mats please post it because I'll definitely give them a try!