These Below Zero socks use the latest fabric technology originally designed for aerospace to prevent your feet getting cold or damp in winter. They’re made of a breathable nylon knit interwoven with soft, fine aluminised threads that reflect your own natural body heat. Perspiration and moisture are minimised so your feet stay warmer and dryer than with normal socks. They’re durable enough to wear on their own or can be worn underneath a second pair of socks.