Sock design begins with foot contour and anatomy. Each part of the foot is addressed with the best possible combination of fitted fabrics. We blend just enough synthetic materials into fine wool fiber for enhanced durability and insulation. We prefer a two sock system to ward off blister friction and offer a variety of thicknesses and heights for both liners and socks. Your boots will fit only as well as your socks do, that's why we designed these to work with the specific shapes of our mountain and pac boots.