This headgear ONLY fits the following Res Med Masks: <li>* Ultra Mirage</li> <li>* Ultra Mirage II</li> <li>* Mirage Micro</li> <li>* Mirage Activa</li> <li>* Mirage Activa LT</li> <li>* Mirage SoftGel</li> <li>* Mirage Quattro Full Face</li> <li>* Ultra Mirage Full Face</li>