Holds the heat very well!
My feet easily get cold. So before going to bed, I fill this water bottle with hot water and slip it under the covers on the area where my feet would be. When I slip under the covers, my feet are warmed up instantly, no more cold sheets! Just be aware of the temperature of the water that you pour into the water bottle. Sometimes, it's too hot and I have to take it off from under the covers. I now find that the right temperature for me is water before it starts to boil. The material is thick and sturdy and doesn't leak when I turn it upside down.
Rating: 5 stars