In yet another preferred embodiment, the source of heated air and the hollow structural member are connected by {HEAD ~ a flexible connection} which permits axial and rotational between the source of heated air and {TAIL ~ the hollow structural member} 
permits rotational between
In yet another preferred embodiment , the source of heated air and the hollow structural member are connected by { HEAD ~ a flexible connection } which permits axial and rotational between the source of heated air and { TAIL ~ the hollow structural member }
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 HEAD OTH REL OTH OTH REL REL OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL