Ever since I was shocked the first time I tried the electric type socks, I swore them off. I don't know if there was a defect in the darn things, or sweating feet, but I went back to my tried and true woolies w/ 400 grams or more of thinsulate. if conditions warrant I'll toss in some chemical foot warmers, and just bite the bullet. Ruined a darn good hunt that particular evening.