The strips are rotated in opposite directions so that corresponding edges are toward each other, and {HEAD ~ the inner face} of one strip and the outer face of the second strip are at {TAIL ~ the top} of the strips 
are at
The strips are rotated in opposite directions so that corresponding edges are toward each other , and { HEAD ~ the inner face } of one strip and the outer face of the second strip are at { TAIL ~ the top } of the strips
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH