The famous holeproof original explorer sock is made from a wool blend And has a dual layer construction. The inner layer is made of a Breathable wool and the outer made out of nylon for longer lasting wear. They have full inner cushioning to provide maximum comfort especially When you’re active. Key features: – Dual layer wool inner for warmth – Nylon outer for durability – Full cushioning for comfort and reducing impact Materials: wool/viscose Style number: SYNX2N