The Orthofeet Arch-booster is bio-mechanically engineered to raise the arch support height, preventing overpronation and painful flat feet. Improves foot alignment, reducing strain of feet, ankles, knees, hip and lower back, and relieving heel and ball-of-the-foot pressure. Place under the heel of any removable insole to enhance arch support. Included with all Orthofeet shoes, except slippers.