A cushion member (2) is for a patient interface device. The cushion member includes a body portion (4) having a first end (6) and a second end (8) disposed opposite the first end, the body portion defining a passage (5) therethrough, and a support portion (10) extending from the second end into the passage. The support portion includes a first portion (12) and a second portion (14) disposed on or in the first portion. The support portion is movable from a first configuration to a second configuration responsive to a change in environment.
