The two longitudinal members 12 and 14 are each formed of {HEAD ~ sections} of hollow cylindrical metal pipe or {TAIL ~ tube}, such as EMT or other reasonably light weight and suitable material of sufficient strength for the purpose 
The two longitudinal members 12 and 14 are each formed of { HEAD ~ sections } of hollow cylindrical metal pipe or { TAIL ~ tube } , such as EMT or other reasonably light weight and suitable material of sufficient strength for the purpose
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD REL OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH