In the closed position, the doors constitute side walls to prevent {HEAD ~ removal} of {TAIL ~ the freight} from the vehicle 
of
In the closed position , the doors constitute side walls to prevent { HEAD ~ removal } of { TAIL ~ the freight } from the vehicle
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH