Composites prosthetics are defined by predefined stiffness of the material and the perception of the composite deformation for the same product is different from one person to another. For this reason, a inflatable composite cover is attached under the prosthetic foot . The role of the cover is to modulate the shock damping but also to increase the contact surface. A big problem in composite prosthetic like the leaf springs for example is that the contact with the sole is never perfect planar, that means an increase in torsion tensions and regional impact cracks. The inflatable composite cover reduce the stress of the structure material. Because the inflatable cover behave like a car rubber tubes it's cost of production is reduced. In my experiment I used bicycle tubes and a elastomer rubber composite to avoid overpressure during inflation.