... : fiberglass, Resin & Fillers 2. Process: Pultrusion 3. Sizes: Custom fiberglass rods, fiberglass bar, fiber glass flat rod (FRP Rebar, Fiberglass Rebar ... , 7.5x20, 9x3.822. Special Size: 6.35x3.175mm fiberglass rods, fiberglass bar, fiber glass flat rod