{TAIL ~ The respiratory conduit} includes at least two air flow control devices, positioned between the patient interface device and {HEAD ~ the pressurized air generating device} 
{ TAIL ~ The respiratory conduit } includes at least two air flow control devices , positioned between the patient interface device and { HEAD ~ the pressurized air generating device }
TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD