{HEAD ~ An actuator} engages the shaft for translation from a first retracted position to {TAIL ~ a second extended position} 
{ HEAD ~ An actuator } engages the shaft for translation from a first retracted position to { TAIL ~ a second extended position }
HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL