A patient interface device includes a fluid coupling member structured to be coupled to a source of breathing gas, and a patient sealing assembly structured to be coupled to the fluid coupling member. The patient sealing assembly includes a central cushion portion, a first side portion and a second side portion, wherein the central cushion portion is structured to enable a size of the central cushion portion to be adjusted in a direction that is generally perpendicular to a longitudinal axis of the patient sealing assembly from a first size configured to provide a nasal/oral mask configured to cover a nose and mouth of a patient to a second size configured to provide a nasal mask configured to cover only the nose of the patient.