The Resmed CPAP is designed to maximize comfort, while automatically delivering the ideal combination of Automatic Positive Airway Pressure (APAP). It contains Expiratory Pressure Relief (EPR) to prevent the collapse of your upper airway during sleep. Now sleep peacefully with the newly enhanced, intelligent algorithm built into ResMed CAP. It works on a sleep therapy system which delivers more effective, accurate therapy for maximum comfort. This special algorithm maintains the ideal air pressure while automatically adjusting through the night to deliver the optimal therapy.