When {TAIL ~ a fluid pressure} in the extension chamber exceeds a certain level, the pressure relief assembly allows {HEAD ~ fluid} to flow through the relief passageway 
When { TAIL ~ a fluid pressure } in the extension chamber exceeds a certain level , the pressure relief assembly allows { HEAD ~ fluid } to flow through the relief passageway
OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL 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