The horizon women s expedition socks are calf length heavyweight walking socks ideal for cold tough conditions the primaloft merino wool blended yarns mean that these socks are super soft warm and comfortable merino wool is a natural fibre which is highly insulating and incredibly soft with wicking properties by adding primaloft to this yarn horizon have created socks that are fast drying and durable this innovative blend is the basis of the expedition socks the reinforced cordura heel and toe