From OOFOS, the Men's OOriginal Sport Sandals feature: Synthetic upper with moisture and odor resistant materials Designed to soothe and reinvigorate feet after a tough workout Proprietary footbed design reduces stress on knees, ankles and other joints Closed-cell foam is machine washable and designed to minimize odor Soft, contouring toe post reduces the likelihood of chafing OOfoam™ footbed cushioning technology absorbs impact, cradles the arch, and promotes natural foot movement Imported.