QDC-501B Alternating Pressure Mattress ismade up by 18 pcs of 11.5cm / 4.5'cells.TheAlternating System includes A/B/C 3 groups ofcells design (6 cells per group). During alternating, there always have 2 groups of cellskeep inflating, it means that it will have 12 cellscan share and support the patient's weight.
