One of the one way valves is located on the inside of one side of {HEAD ~ the barrier bag}, and the other of the one way valves is located on {TAIL ~ the outside} of the other side of the barrier bag 
One of the one way valves is located on the inside of one side of { HEAD ~ the barrier bag } , and the other of the one way valves is located on { TAIL ~ the outside } of the other side of the barrier bag
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH