a nasal delivery interface system fluidly connected to {HEAD ~ the fluid control system}, said {TAIL ~ nasal delivery interface system} including a single scavenging tube and a single nitrous oxide and oxygen tube fluidly connected to a nasal delivery mask 
a nasal delivery interface system fluidly connected to { HEAD ~ the fluid control system } , said { TAIL ~ nasal delivery interface system } including a single scavenging tube and a single nitrous oxide and oxygen tube fluidly connected to a nasal delivery mask
OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH