{HEAD ~ A ring} is rotatably mounted to the cylindrical top and has {TAIL ~ three notches} defined in an inner periphery thereof 
has
{ HEAD ~ A ring } is rotatably mounted to the cylindrical top and has { TAIL ~ three notches } defined in an inner periphery thereof
HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH