{TAIL ~ The pressing device} presses the retractable unit toward {HEAD ~ the open position} in which the unit is extended 
{ TAIL ~ The pressing device } presses the retractable unit toward { HEAD ~ the open position } in which the unit is extended
TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH