Single-limb, Vented, Anti-asphyxiation Valve Key Features A vented mask to help with ease of care by removing the risk of confusion around exhalation port set up. RollFit™ seal adapts to different face shapes and minimizes pressure on the bridge of the nose TubeFit™ zones for placement of a nasogastric or orogastric tubes ErgoFit™ with easy clips and breathable fabric to help with fitting and adjusting Available in four mask sizes: extra small, small, medium and large