These are extremely dense, warm woolen socks. Wore snowshoeing for hours in near-zero temps, no blisters, no sweating, no cold feet, no problem. Also breathable, and for some reason, scent-resistant. Wore for several outings without washing and did not smell at all. Also bought hats and mittens - just cannot get any better! A huge thank you to the Dachstein company for continuing to provide excellent traditional warm woolenware!