A patient interface structure for delivery of respiratory therapy to a patient includes a cushion assembly that has an elastomeric piece with a mouth seal portion configured to seal around the patient's mouth and a nasal seal portion configured to seal against at least an underside of the patient's nose. The cushion assembly also has a cushion clip attached to the elastomeric piece and forms at least part of a plenum chamber with the elastomeric piece. The cushion clip is more rigid than the elastomeric piece. A front plate that is more rigid than the elastomeric piece and has a plurality of headgear attachment points is attachable to the cushion clip by way of a snap fit connection. A gas passage extends along a surface of the front plate and includes an inlet opening configured to connect to an air delivery tube or a connector for an air delivery tube.