The containers 12 and beams 14 may be made from {HEAD ~ a variety} of {TAIL ~ materials}, including metals, composite material, ceramics and plastics, but are preferably rigid and light weight 
of
The containers 12 and beams 14 may be made from { HEAD ~ a variety } of { TAIL ~ materials } , including metals , composite material , ceramics and plastics , but are preferably rigid and light weight
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH