I handled the sock to a friend to show him what i received today, and he said, "whatttt, its like walking on a cloud". They definitely keep you warm, and if your feet are like mine, where they get cold easily then you should give these a shots. I can now wear some of my favorite shoes/boots that aren't good for 20 degree weather. I have noticed when its not cold in my room and while i wear these, they tend to sweat the upper part of my feet, the ankle and above. i also sweat in these while dancing. But you cant tell until you start taking them off.