Maximum support for running and walking, Orthaheel technology helps reduce over pronation, which can relieve pain in the knee, heel, legs and back. Fits in most shoes with removable foot beds. This insert is comprised of a polypropylene shell for maximum support. The top covers are designed to reduce friction while providing ample cushioning for the foot. Extra Soft Poron inserts at the heel and ball of the foot help absorb shock and increased overall comfort.