By fusing together low-micron merino wool and polypro fibers, you get an incredibly strong yarn that allows the Kenetrek Montana Midweight Socks to act like heavyweight socks in both warm and cold climates. They're strong, wicking, odor and blister resistant, breathable, quick drying and they immediately recover in the wash. When the weather is a little less extreme on either end of the spectrum, reach for these.