It can be seen that two clips 18 are locked to the exterior and intermediate sheets 15 and 16, and {HEAD ~ the clips} 18 at {TAIL ~ their corrugations} 22 are locked to the sheets 16 16 and 17 17 
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It can be seen that two clips 18 are locked to the exterior and intermediate sheets 15 and 16 , and { HEAD ~ the clips } 18 at { TAIL ~ their corrugations } 22 are locked to the sheets 16 16 and 17 17
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 OTH REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH