The plastic seems pretty lightweight and not very rigid. I don't think this mat is suitable for anything other than a hard surface floor. When used on carpeted surfaces this mat will show indentations from your chair legs/wheels.
The size is nice and I like how it stays in place but it's too soft when you sit in a chair and try to move. A firmer mat would have been more desirable. Wished I could exchange it for a firmer mat.
After taking three days of having dumbbells resting on the mat to straighten it we are finally able to use it in our home office. The mat is not as firm and rigid as I would like as the wheels from our office chair sink down in the mat and carpeting.
Good for the short time but will need something heavier duty for the long haul. Good enough on short notice. Will definitely buy from Staples again. Great delivery and great service as always.