The APM 440 alternating pressure system is suited for the treatment of pressure ulcers up to stage IV (according to EPUAP). The control unit is equipped with a digital sensor control, which regulates the inner pressure of the mattress, creating a perfect surface pressure. Again, the use of two compressors guarantees safety in case of a compressor malfunction. Adjustment is accomplished with the aid of a touch pad surface, equipped with visually easy to comprehend pictograms. The result is a quick and easy operation. The alternating mode offers three separate time cycles. In addition, a permanent (pressure-reduced) static mode can be selected for the therapy of pain patients, as well as a care mode, which simplifies care and mobilization. Once in a care mode, all mattress cells are inflated for 30 minutes. This significantly simplifies the re-positioning and the care of patients. The automatic key pad lock is activated after three minutes preventing an unintentional "re-adjustment" of the control unit. The mattress cells are 20 cm high, with 7 extra slim heel cells. This allows the patient to sink deeper into the mattress surface. As a result, patients weighing up to 180 kg can be positioned. Each cell is equipped with a CPC quick coupling, permitting an ultra-fast cell exchange or cell removal to freely position the patient. The transportation safety lock maintains the system inflated, thus guaranteeing a safe transport of the patient. As an additional safety measure, our mattress substitution system is equipped with a 3.5 cm high base mattress.