Good pre-loved conditions. See photos. Questions? Comment below! The OOFOS story begins with the OOriginal Sandal. This combination of sleek design and revolutionary OOfoam™ recovery technology lays the groundwork for all future styles and models. Revolutionary OOfoam technology absorbs 37% more impact than tradition foam to reduce stress on feet, knees, and joints. These dreamy-soft sandals are designed with strategic arch support and a diamond-grid footbed pattern to promote natural motion.