Ehob Waffle Air Cushion Foot/Heel Protector Boot suspends heel for reduced pressure. The two air chambers protect the entire lower extremity by elevating the heel and cradling the calf to promote circulation. The air venting holes and soft, cloth lining keep skin dry and comfortable. The outer covering is non-abrasive, medical-grade vinyl that permits movement without resistance. The foot cradle provides stability while reducing lateral rotation and brings the ankle up to zero degrees to prevent foot drop. The ook and loop closures allow quick application and adjustment for a perfect fit. The PRN strap can be opened or closed depending on patient needs. You can find the size by measuring calf circumference.