This is a single full face cushion and clip in the selected size. The Quattro cushion, cushion clip and mask frame are sized and all must be the same size to work as intended. Extra small cushion and clip with extra small frame Small cushion and clip with small frame Medium cushion and clip with medium frame Large cushion and clip with large frame This cushion is compatible ONLY with the original Quattro Full Face Mask. It is NOTcompatible other versions of the Quattro mask or any other ResMed Mirage masks. The cushions and clips are not interchangeable between masks.