Iris Track Nubuck Mix is made of calfskin and with real wool lining. All leather is from LWG certified production. The boot is completed with a distinctive track sole. The insole is made of a soft PU-foam material, which is both light and shock-absorbing. It is covered with WODEN cork, to ensure breathability. The outsole is based on our Natural Soft technology. A technology designed to ensure you the best comfort. The outsole also consists of 65% natural rubber, 10% recycled rubber, and 25% conventionally produced rubber. Iris is a comfortable companion on the move.