A respiratory interface device provides a support cushion (15) including a cushion body (20) and at least two inserts (50). The cushion body has a plurality of stiffener passages (22). The at least two inserts are stiffening inserts shaped to correspond to the stiffener passages. The cushion body is made from a first material having a first hardness. One of the at least two inserts is made from a first material, having substantially the same first hardness as the cushion body, and the second insert is made from a second material having a second hardness, the second hardness being different than the first hardness.