{HEAD ~ The end supports} can allow {TAIL ~ the extended barrier member} to move in a direction transverse to the width of the barrier member when desired 
{ HEAD ~ The end supports } can allow { TAIL ~ the extended barrier member } to move in a direction transverse to the width of the barrier member when desired
HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH