Sitting improperly can affect how you back feels in general or it can aggravate an existing spine or muscle problems or injury. The Original Tush Cush is a portable coccyx support seat cushion that goes anywhere and can be used on any surface. It improves the angle of your sitting posture significantly and relieves the pressure at the coccyx. It does this by raising the base of your spine. While your thighs and buttocks rest on the wedge shaped foam cushion, your coccyx (tail bone) is positioned over the cut out. This assures that your coccyx rests only on air.