{HEAD ~ A lock} having {TAIL ~ the duress feature} would substitute a duress tumbler wheel assembly for one of the tumbler wheel assemblies  
{ HEAD ~ A lock } having { TAIL ~ the duress feature } would substitute a duress tumbler wheel assembly for one of the tumbler wheel assemblies
HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH