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