Unsaturated Polyester Resin Fiber Yarn Pultrusion Material 830 Class B This product is made of non-alkali glass fiber yarn impregnated with unsaturated polyester resin by the traction force and finally pultruded and solidified in hot mold. It is mainly used as insulation components of electrical equipment. The product can be rectangular, I-shaped, angular, T-shaped, groove-shaped, tubular and cylindrical, etc.