It is a nice heavy mat but dents easily and leaves ruts for my chair to roll into. I have to keep moving to a new spot on the mat. The carpet is in fact 3/8 Berber. I am 220 lbs. Probably sending it back.
I love the matt but was very disappointed how it was when delivered. It wasn't rolled up it was bent so I had to put a tote on it for 3 days to flatten it.
Despite the multiple projections on the bottom th e mat creeps to one side over a few days but does protect the carpet and the rolling chair moves easier