This high risk, active mattress comes with a built in underlay mattress which provides an extra layer of comfort incase of the 16 alternating cells collapsing. Supplied with a pump, this runs on a 10 minute cycle to ensure gentle movement of the patient to avoid any pressure sores. The watreproof cover ensures easy cleaning, but is comfortable enough to allow a good night sleep for the patient. With a 3 year warranty, and the option to replace individual ceels this product is designed to last a long time.