Haysite Reinforced Plastics Haysite Reinforced Plastics, located in Erie, PA, is among the worldwide leaders in the formulation and processing of thermoset composite materials. Since 1954, Haysite has been at the forefront in technological advances in fiberglass reinforced products. Offering the broadest product line in the industry in laminated sheet, custom molded parts, pultruded shapes and molding compound, Haysite maintains its competitive advantage through unparalleled product innovation a...