Uppers: Faux Leather or Natural Cork. Footbed: Microfiber wrapped EVA, absorbs shock, reducing stress on feet, ankles and knees. Outsole: Durable rubber with a patterned tread provides traction on a variety of surfaces. Orthaheel Technology is biomechanically designed to hug your arches and support your feet in comfort. Vionic sandals' built-in orthotic is shown to be effective in helping to treat heel pain (plantar fasciitis).