A cross sectional shape of each striation is an isosceles trapezoid having an upper base at the face side and {HEAD ~ a lower base} at {TAIL ~ the back side} of the golf club head 
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A cross sectional shape of each striation is an isosceles trapezoid having an upper base at the face side and { HEAD ~ a lower base } at { TAIL ~ the back side } of the golf club head
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH