Our Primaloft Lightweight socks utilize Primaloft polyester yarn to keep your feet warm in a variety of temperatures, all without overheating or being excessively bulky. - Calf High--18cm/7in with seamless toe construction. - Great for transitional weather and offers great moisture-wicking and thermal regulation. - Primaloft polyester yarn offers the best thermal performance to weight in a wide temperature range. - Soft terry-loop footbed and toe provide comfort and warmth for transition weather. - Made in Italy.