Therm-ic Warm Reflector fibre reflects and retains the warmth generated by your feet; Merino wool - high-quality, fine, warm, soft wool for efficient heat conservation; Sock's technical construction wicks away sweat for fast drying; Reinforcement on heels and toes; Protection: scuff guards on shins, calves, calves and instep; Micro-ventilated arch to wick away perspiration; Special construction for left and right feet for better foot support; Knee height