The first and the second blocks are formed in {HEAD ~ a center area} of {TAIL ~ the tread surface} between the two third main grooves 
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The first and the second blocks are formed in { HEAD ~ a center area } of { TAIL ~ the tread surface } between the two third main grooves
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 OTH