Plates and slabs not of metal, namely, cement slabs, natural stone slabs, non-metal paving slabs, non-metal slabs for building, non-metallic reinforcements for concrete and wood building construction in the nature of plates; tubes, namely, non-metal, rigid filtering tubes used to prevent storm water runoff pollutants from entering sewer systems; pipes and connecting parts not of metal whether protected or not by an inner lining, namely, non-metal pipe couplings and joints, rigid pipes not of ...