A lightweight oxygen delivery device for a patient comprising an elongated tube, releasably connectable to an oxygen delivery source at one end and to a rigid elbow at the other. The wall circumscribes a centrally positioned oxygen outlet communicating with the tube through the elbow so as to receive oxygen from the elbow and direct the flow of oxygen delivered from the elbow generally towards the patient's nose and mouth. Flexible wings are secured to the tube, between its ends, the wings extending outwardly to either side. An elongated flexible strap is secured to and extends between the wings, the strap to extend around a patient's head and secure the wings in position to hold the diffuser proximal to the patient's nose and mouth.