Mephisto Helen Spark sandal has a sole unit is composed of 100% rubber with air injection, for added flexibility. The shock absorbent soles reduce foot, and leg strain. Cement construction for increased durability. Footbed is composed of a mixture of cork and latex, to provide maximum support, and shock absorbency. With built in arch and metatarsal support, this sandal is medium/wide fit but accommodates a deep foot with the adjustable strap over the instep area.