The RoToTo Trail Magic Socks have been developed for one of the designer's friends, who's a professional trail runner. The prototype of these RoToTo socks was used for the one of most severe trails in the world, Continental Divid Trail (5000 km). Any damaged parts were then investigated and developed further to make the product more durable. Mixing shrink-resistant Merino wool and special stretch yarn, as well as arch support plus the three-dimensional structure add comfort and durablity to the RoToTo Trail Magic Socks. Enough even for a long trail run. 79% wool, 13% polyester, 5% nylon, 3% polyurethane.