This nasal cushion from Respironics is designed for use with all Pico CPAP Masks. There are three cushion sizes available -- Small/Medium, Large & Extra Large Pico's soft nasal cushion fits over just the tip of the nose so it requires very little facial contact. The dual-wall design features an inner wall that seals softly against the face and an outer wall that provides support and stability. Pico's cushion is simple to fit without leaks or pinching; and it adapts automatically to different sleep positions and movements so you can sleep comfortably. Please note that Pico's soft cushion is permanently attached to the hard, clear shell. The two pieces cannot be separated. Any cushion size will fit on any Pico CPAP mask frame so if you find you want to try a different size you can simply purchase a new cushion rather than having to buy a whole new mask.