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