{HEAD ~ A locking device} will lock {TAIL ~ the tieback member} to the groove in the wellhead housing 
lock
{ HEAD ~ A locking device } will lock { TAIL ~ the tieback member } to the groove in the wellhead housing
HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH