EIA-CES BME program in collaboration with Mexico's Universidad iberoamericana has been able to design and fabricate contoured seats according to Centro de Ingeniería y Tecnología de Rehabilitacion (CITeR) protocols. The use of common foams increases seat deterioration and changes pressure maps. New materials such as polyurethane have been used to improve functionality by means of increasing flexibility. The objective of this study was to identify this material optimal Young modulus to ameliorate the shaped seats functionality. Foam flexibility increased with the addition of polyurethane.