{TAIL ~ Barriers} are coupled mechanically to {HEAD ~ the parallelogram members} so as to deploy when the lift is first displaced from its stowed/retracted position 
{ TAIL ~ Barriers } are coupled mechanically to { HEAD ~ the parallelogram members } so as to deploy when the lift is first displaced from its stowed / retracted position
TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH