Four points of adjustability on this backstrap sandal deliver completely customisable comfort. Two square enamel trim beads add interest to the top of the vamp. Upper: Man-Made or Natural Cork. Footbed: Microfibre Wrapped EVA. Outsole: Durable Rubber. Our innovative podiatrist-designed FMT Technology provides superior orthotic support relief and stability which helps realign the feet back to their natural position. Research supports FMT Technology's success in reducing over-pronation which can help relieve associated common aches and pains such as heel pain (plantar fasciitis) knee pain and lower back pain.