Abstract: A shock absorbing device comprising: an upper impermeable sheet; a lower impermeable sheet; an intermediate flexible impermeable sheet which is deformed to provide a grid of spaced peaks projecting on each surface thereof, the peaks being fixed to the upper and lower sheets to form two chambers of interconnected pockets, the upper one chamber being filled with a non-compressible liquid and the lower other chamber being filled with a compressible gas, the liquid and the gas being sealed therein.