This is the replacement, silicone nasal cushion for use with the DreamWisp Nasal CPAP Mask. The DreamWisp mask utilizes a minimal contact nasal cushion design for exceptional fit and comfort. The nasal cushion is available in 5 sizes. The DreamWisp universal frame and headgear design allow any size DreamWisp cushion to fit. So, you can try any size cushion, and it will fit the mask frame.