19 construction elements not made of metal, namely, supports for rebar and formworks; non-metal stirrups for concrete reinforcement and formworks; non-metallic reinforcements for concrete and wood building construction, namely, closed-loop rods and bars; non-metal forming systems for concrete and other curable construction materials comprised of non-metal modular casting forms; reinforcing materials, not of metal, for building; non-metal rebar used for strengthening and reinforcing concrete structures and formworks