Arrived at scheduled day. Good sturdy plastic mat. I recommend this mat. Check the carpet-mat thickness table before ordering. The table is very useful as it guides which mat type to purchase.
The mat arrived rolled up tight and has refused to flatten out for multiple weeks. There have been weights on various areas of the mat the entire time without success. If you take a weight off of the edge and it appears to be almost flat it will be curled up again the next day. My only hope may be to wait for a hot sunny day and lay it outside in the sun for the entire day. The mat may be OK if it ever flattens out.
I'm 180 lbs sit on a standard 5-leg office chair. Mat sits on a 1/4" deep wall to wall rug.Sitting still 15 minutes at desk leaves a dimple under front wheels that's difficule to roll out of. Totally unsatisfactory. I have already ordered a replacement(tempered glass). It's like the plastic wasn't cured. My previous mat was thinner and totally satisfactory but too small(3x4)- kept rolling of the edges. This one is almost 50% thicker(0.1 vs 0.145) but much less supportive. I was suprised - and dissappointed.