These things work as expected. The intent is to keep your feet at body temperature. I just used these over the weekend on days where the temperature was ZERO... they worked. I like the fact there are no wires (I have ski boot heaters with wires and BIG batteries). The smartest way to use these insoles is to put them on medium to get the maximum time.
My Husband uses these for hunting. He says that they keep his feet warm while sitting for a long period of time, They are not hot, just right . But the sizing could be better as he has to push them to the front for his toes, but it does not bother him or feel funny in his boots when walking.
I ride a bike in the morning and these certainly take the chill out of the toes. They are thin and fit well into the shoe without taking up too much room. They stay a nice even temp. They do not stay warm as long as the package says but still happy. The vendor had a great price and delivery was fast.
Can't say enough about this product. I have been wearing thee for the past 4 years. I don't spend one day between November and March without these in my boots. I put them on in the morning and they last all day. I am in my late 50's and I work outside; by wearing these my circulation stays good and my toes don't get cold. My son lives in China and he wears them with the same results, and it gets a lot colder where he lives. GREAT PRODUCT!
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