I will never buy another type of rug pad again.  When I opened it I was skeptical as it weighed nothing…I looked at the insert in the package where it explains the two different sides.  I tried it both on a bare floor for a few days and then on carpet (where I really needed a good holding rug pad) and it works like a dream!  I will be ordering several more and replacing all of the ones that I have eventually.  It’s worth the money.  Don’t hesitate to purchase this…