Sizewise pulsation therapy is a patented technological advancement in true low air loss. Pulsating advance feature automatically adjusts each of its five zones for changes in patient comfort and pressure redistribution. The gentle stimulating action aids in the increasing capillary blood flow to skin. The top cover is customized to lessen friction and shear. It also facilitates in moisture regulation by allowing air to move in and out through, keeping the patient dry and cool thus maintaining its waterproof characteristics at the same time.