The DeVilbiss SleepCube AutoAdjust Plus Auto CPAP has the same great features and design that made the regular SleepCube so popular, but now they’ve added SmartFlex* exhalation relief. SmartFlex allows the CPAP machine to reduce the pressure during exhalation, making it more natural and comfortable. Add this to a feature list that includes quiet operation, a compact design, one of the most convenient humidifiers available (optional) and a three-year warranty. You have one of the best all-around machines available.