Presently it is -4 degrees and I have two Insulated cat shelters. Both have one extreme weather kitty pad in each with dry straw. The cats have cleared away the straw from the pads and all you can see is a perfect circle over the pads where the cats will sleep. The cats have their heads out the door of the shelter, but are glued to the comfort of the pads...I have had the pads for two years now with no issues..They work great..