Water mattress made in PVC with a stabilising inflatable external structure to prevent excessive water "wave motion" and of 3 independent units. The water mattress distributes the total pressure on the whole supporting surface, making this less than the average arterial pressure, avoiding the exposure of the skin to pressure risk. Easy to use, it is placed over the usual mattress and it is washable. It is sold with a manual pump and an inflation tube. Size: 190x85 cm Weight: 4 kg PVC thickness: 0.4 mm