It is a Swedish-made two-layer felt that is 100% recyclable. Wool warms, absorbs moisture well and is nice to wear in your shoes. Wool also heats well when it is moist. The wilt layer is there to provide damping to the sole. The materials are Wool, Polyester and Viscose. Wool is a natural fiber. Polyester is a thermoplastic, Viscose is cellulose-based.
The felt is produced in Sweden, from fiber to finished product, in a clean & dry process without additives. The supplier has 100% traceability on input fiber.