Small, quiet, and totally integrated.With the Z1™ the intent was to deliver the most portable CPAP machine available. At 45% lighter and 37% less volume than the closest competitive device. We think we achieved what we set out to do: Reinvent CPAP. One of the greatest issues cpap users complain about is the difficulty in exhaling against the pressure exerted by the cpap machine. The Z1™ cpap machine uses our proprietary Z-Breathe™ algorithm that learns from your breathing pattern and relieves machine pressure on exhalation.