FIG 1 shows an example in which {HEAD ~ the present invention} is applied to {TAIL ~ an iron golf club head} 
is applied to
FIG 1 shows an example in which { HEAD ~ the present invention } is applied to { TAIL ~ an iron golf club head }
OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL