Part of Vionic's Tide Heritage Collection, Casandra has a feminine perforation and a variety of color options. Helps alleviate heel pain. Uppers: Leather. Lightweight, flexible medium-density EVA midsole absorbs shock, reducing stress on feet, ankles and knees. Vionic 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. Outsole: Durable Rubber. Received APMA Seal of Acceptance.