Feel the OO - The OOFOS shoe story begins with the OOriginal Sandal. The combination of sleek design and OOfoam recovery technology laid the groundwork for all future OOFOS styles and models. OOfoam Technology - Our revolutionary OOfoam technology absorbs 37% more impact than traditional footwear foam materials to reduce the stress on your feet, joints & back. Plus, the closed-cell foam is machine washable and designed to minimize odor. Patented Footbed - Our patented footbed cradles and supports arches to reduce energy exertion in the ankles by up to 47% compared to competitors’ footwear. So walking is easier. Recovery is faster. And yOO feel better. Backed by Science - Research shows OOFOS reduce load, decrease compressive forces, and support foot mobility when compared to traditional footwear. As a result, every OOFOS style carries the American Podiatric Medical Association Seal of Acceptance! Made for Recovery - When you’re always on the go, the demand on your joints can translate into fatigue, muscle tightness & pain. At OOFOS, we don’t want to slow you down. Our shoes are designed to help your body work less—so you can do more. Finding Your Size - For your perfect fit, consult the sizing chart in the images above! Wear a half size? In general, we recommend that women who wear a ½ size size up, and men who wear a ½ size size down.