Tempur Seat Cushions are constructed of a high quality visco-elastic, temperature sensitive open cell material which has unique pressure relieving qualities. Unlike ordinary polyurethane which features irregular cell shapes that simply compress under weight and degenerate over a short period of time, the TEMPUR Pressure Relieving Material is composed of billions of visco-elastic spherical shaped, open cells. The cells respond to body temperature and weight then shift and reorganise their position to mould to the exact contours of the patient's body