KLIM Vented Sock SM Gray Highly breathable moisture-wicking Coolmax yarn Terry knit for comfort padding at ankle, heel, forefoot and sole Zonal padding at ankle, heel, forefoot and sole Nylon reinforced toe, heel, sole 55% Coolmax, 41% polyamide, 4% Lycra *note that the use of a technical sock is required to obtain the full functionality of Gore-tex boots.