Thus, {TAIL ~ a gas} may be delivered from a gas source through the gas tubing, swivel coupling, and {HEAD ~ cannula} to a patient without tangling or twisting the tubing 
Thus , { TAIL ~ a gas } may be delivered from a gas source through the gas tubing , swivel coupling , and { HEAD ~ cannula } to a patient without tangling or twisting the tubing
OTH OTH 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 OTH OTH OTH OTH OTH OTH OTH OTH OTH