Here, {HEAD ~ lands} 4 are divided into {TAIL ~ one third and two thirds sections} from alternating ends on adjacent lands 4 
Here , { HEAD ~ lands } 4 are divided into { TAIL ~ one third and two thirds sections } from alternating ends on adjacent lands 4
OTH OTH HEAD HEAD HEAD HEAD HEAD OTH REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH