OOFOS Unisex Original Thong flip flop, Steel, 7 M US Women /  5 M US Men's 100% Synthetic Imported Oofoam sole OOfoam Recovery Technology absorbs 37% more impact than traditional footwear foam Patented footbed cradles your arches to reduce stress on sore feet, ankles, knees and lower back Biomechanically designed to allow natural motion Machine washable