Designed for ideal support and comfort following trauma or post-operative procedure. The lightweight design and pre-shaped ergonomic frame help to modify the level of pressure on the injury at both the malleoli and lower leg.. The soft nylon/foam liner has an integrated pump design making the pneumatic liner simple to inflate and adjust.. Medium size fits those who wear men's shoes, size 7½ – 10½ or women's shoes, size 8½ – 11½..