Thus {HEAD ~ the locking device} is not accessible from {TAIL ~ the outside}, so it cannot be damaged or operated by an unauthorized party 
is not accessible from
Thus { HEAD ~ the locking device } is not accessible from { TAIL ~ the outside } , so it can not be damaged or operated by an unauthorized party
OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH