Fisher & Paykel Zest Nasal CPAP Mask without Headgear ResMed CPAP Supplies Many users can relate to Power Built in Rechargeable Many users can relate to the fact that when you change position you might cause a leak in the mask seal which results in therapy pressure escaping Perfect patient ventilator synchrony for the most efficient and comfortable therapy Many users can relate to the fact that when you change position you might cause a leak in the mask seal which results in therapy pressure escaping It is recommended to clean the seal of this mask daily to prevent dirt and oil build up which can compromise your mask seal