A helical insert or {TAIL ~ key lock insert} may be utilized as {HEAD ~ the inserts} 82 
A helical insert or { TAIL ~ key lock insert } may be utilized as { HEAD ~ the inserts } 82
OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH