"Never had boots that kept my feet warm; not even battery powered ones. I absolutely love/recommend these omni-heat boots. I suffer hypothyroidism. Feet are always cold; not with these boots. Feet were toasty all day. Minnesota winters are extremely cold but, no problem keeping my feet warm in these boots. Daily activities, or, riding the snowmobile, my feet were always warm..Omni-heat is the best yet!"