a structure , box or hopper for transportation which is formed from a combination of polymers and steels . in one embodiment , polymers comprise the body of the hopper which is in direct contact with the load being transported . in this way , the polymers bear the impact and wear and tear caused by the material being transported . the present invention further comprises various systems for fastening the steel portion of the hopper to the polymeric portion including the use of adjustable elastomeric ropes for supporting a weight bearing rubber mat .