When {HEAD ~ the collection swab} is inserted into {TAIL ~ the transport tube}, the swab pushes the rehydrated media plug through the region of restricted diameter and into the bottom of the tube 
is inserted into
When { HEAD ~ the collection swab } is inserted into { TAIL ~ the transport tube } , the swab pushes the rehydrated media plug through the region of restricted diameter and into the bottom of the tube
OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL 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