We donate 5% of the sales of this sock to help support the Appalachian Trail Conservancy's outdoor education programs and maintenance of America's first national scenic trail. Cushioning along the bottom of the foot provide the perfect amount of support while a smooth, performance fit assures there's no slipping, no bunching, and no blisters. Fine gauge knitting makes this Merino Wool sock a true workhorse that's supremely comfortable, breathable and fast drying. Cool in the summer, warm in the winter and naturally antimicrobial so it repels bacteria and odor, which comes in handy when you need to get an extra day (or two) out of your socks. Still made in Vermont. Guaranteed for life. Merino Wool - Darn Tough custom count, shrink treated Merino wool enhances the comfort and durability that outdoor enthusiasts have come to expect from this fiber. True Seamless - Using the latest generation of Italian knitting machines, Darn Tough are able to knit ultra-light yet extremely dense socks with an undetectable toe seam, here in Vermont. The result is miles and miles (and miles) of blister-free bliss. Feel the difference of feeling nothing at all!