Furhaven Self-Warming Mat for Dogs Beds & Blankets, Electricity-Free & Reflects Body Heat - ThermaPup Reflective Thermal Insert - Silver, Jumbo/XL...

It's fairly sturdy but if you have a chewer they will chew through the cot part, which is replaceable but just wish it was alittle more reinforced in the corners.

I ordered a couple of these to put on my couch because my house is cold at night and I hoped this would encourage my very big cats to sleep there for warmth instead of in my bed and on top of me. After laying these out on the couch and covering them with a wool blanket, I decided to lie down for awhile (1/2 an hour) to test them out. Not only are they hard and uncomfortable, they didn't generate any warmth whatsoever. Too bad cats and dogs can't write reviews or tell their parents that these thinks don't work and they're still cold!

I like it my dogs not so much.

Great addition to a dog house! Cannot have materials that trap water. Hay is one of best beddings to use, blankets trap water (I would much rather have a dog inside). Water repels off silver parts of this product. Silver part is same as those emergency blankets they have for humans. The edges where black foam is at between two silver sides could potentially get moisture in them, ideally you could cover this in tape maybe if worried. A dog I know that lives outside, this I was able to fit inside her dog house with extra material to spare, so I wrapped it up the edges and back of dog house, adding more insulation/potential to reflect body heat. I got biggest size knowing I could cut it down, but didnt need to. It definitely would have been easy to cut if needed. I am glad I was able to add potentially more insulation/reflect body warmth for this outdoor dog. She was thrilled with dog toys I brought her too! Hopefully she learns to use the new clear door on house (owners notified to monitor).