This Headgear with Arms, from Respironics, is designed for use with all DreamWear Nasal and DreamWear Nasal Pillow CPAP/BiPAP Masks. The arms of the headgear are designed to sit similarly on the head as arms of eye glasses would, and then connect into the headgear frame itself. This headgear option is more stable and slip resistant due to the arms, creating less mask and headgear movement throughout the night which in turn eliminates mask leakage allowing you sleep more soundly.