In one embodiment, the corrugation have a pitch of five inches and a height of one half inch; in another embodiment, {HEAD ~ the pitch} is {TAIL ~ six inches} and the height is one inch 
In one embodiment , the corrugation have a pitch of five inches and a height of one half inch ; in another embodiment , { HEAD ~ the pitch } is { TAIL ~ six inches } and the height is one inch
OTH OTH OTH OTH 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 REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH