Fit & Design: Supportive performance fit mid-calf socks Nylon/FRI nylon blend offers strength, durability and heat with rubber and elastic for optimal resiliency Low volume for less bulk in your boot Technology: Sweat-wicking technology provides all-day comfort Lightweight hollow fibers embedded with permanent oxide minerals harness the body's far infrared energy to generate gentle warmth Active carbon embedded into fibers provides enhanced thermal regulation and odor blocking properties Additional Details: Suggested care: Machine wash cold; do not use bleach, brighteners, or fabric softeners; tumble dry low; do not iron; do not dry clean; wash in between wearing