Oofos Unisex Ooriginal Thong Sandals,Black,6 M US Men / 8 M US Women Synthetic Synthetic sole Ultimate comfort in a stylish slip on thong sandal Soft, durable and provides extra-cushioning and shock absorption Reduces the impact of walking on hard, unnatural surfaces to help prevent foot fatigue Made with the patented OOfoam so lightweight and machine washable Great for sore or arthritic feet