I had bought three of these mats. They say that they are for carpets 3/4" thick including pad. I measured by sticking a paper clip into the carpet. I came to just 3/4". These mats are so thin my chair sinks into the mat and makes it difficult to roll across. When I do try to roll the mat will shift and pucker when it bumps into a file cabinet. I have to straighten them out a couple of times a day. I would have returned them but I am 72 years old and it was a major task getting them into my office in the first place.
The add was misleading. First it was not thick enough for high pile carpet.My chair made dents right away that where hard to get out of after just 1 hour. Second the points on the bottom are not long enough. I have to preposition it at least 3 times a day. This mat at best for low profile carpet.
The mat wasn't rolled when delivered and had some lumps but it flattened right away. It helps my chair glide while protecting the carpet underneath as I had hoped and looks good.
This does not have to sharp pointy pins on the bottom. As a result it slides on the carpet and every few days i have to pull it back where it belongs. Wish at least some of the pins on the bottom were the sharp ones. They stay put.