Abstract: A mattress having an integral air system responding to a load pressure. Included are a pump body (1), an air reservoir (2), air pipes (7), one-way valves (3), a manually adjustable pressure regulating valve (5) provided with a scale (6) and an insulated air cell (4). The pressure is maintained in air cell (4) when air is being squeezed from pump bodies (1) and pushed into the unpressurized reservoir (2) by way of the one-way valves (3) when a user of the mattress creates a zone-wise load pressure. The compressed air in reservoir (2) remains as a reserve therein and equalizes the in air cell (4) dropping pressure having been lost due to diffusion. The equalization is controlled by a need adjustable pressure regulating valve (5) having an adjusting knob (15) and a scale (6) thereon. The thus manufactured mattresses are adjustable in their support capabilities from soft to hard. The mattress can thereby be matched to the needs of a user.