The new ResMed Quattro FX Full Face CPAP Mask system offers a completely unobstructed field of vision. The Quattro FX rests atop the bridge of the nose so it will not interfere with one's view. The lightweight mask rests gently on the face and runs quietly to ease the wearer into a restful sleep. Plus, the full face mask system has the Soft Spring Air cushion technology ensuring the mask stays on the face, regardless of movement, evenly distributing pressure and maintaining the air seal. The Quattro FX mask covers both the nose and mouth eliminating pressure loss from the mouth while breathing. This is a helpful mask for people suffering from nasal congestion or allergies. Available in 3 convenient sizes: Small, Medium, & Large.