It is a combo of 03 pieces i.e. head, torso and foot section. 
Standard Size (Head Section):  225 X 500 X 12 mm; (Torso Section): 990 X 500 X 12 mm; (Foot Section): 500 X 500 X 12 mm; [L * W* H] mm in which L = Length; W = Width and; H= Height  in milimeters. 
Maximum pressure redistribution preventing bed sores among all three body divisions & such pressure redistribution prevent bed sores, pressure, shear and frictional impact