Product review (1 stars): Not what I expected
The slippers run small - I wear an 8 shoe and my heel sits on the back. Also, the heat is concentrated in one area and burns the bottom of your foot.  I was hoping these would work as I have no insulation on the floor of my office as it is a utility building.  It isn't worth the time to send them back - will take out the heater part and voila - the dog has a new toy.