Reach Your Highest Peak: The Most Technologically Advanced Sock for Hiking and Trail Runs. Designed to provide your feet with advanced stability and support so you can get the most out of your next trail adventure. Swiftwick FLITE XT Trail features AnkleLock Technology that supports your ankles during quick movements on uneven & varying terrains, while GripDry Fibers in the heel and forefoot keep your feet from sliding in your shoes. But, we didn't stop there - we blended natural Merino Wool with a full Olefin fiber footbed to move moisture away from your feet, keeping them dry and blister-free even during the longest of treks. - Made in USA