The replacement cushion for Eson 2 Nasal CPAP Mask is an updated cushion that creates a more reliable, effective seal. The RollFit feature on the cushion allows users to roll the cushion back and forth to reduce pressure and find the proper angle. Only the cushion is included, other mask parts can be purchased separately. This cushion is not compatible with the original Eson Mask. It will only work with the Eson 2 Mask.