This specification covers two styles of glass cloth impregnated with a polyester resin system, wht resin being processed to a "B" stage condition. Either style of glass may be used.These products have been used typically for laminates requiring high strength and long-term heat resistance up to 70 degrees C (158 degrees F) and fabricated by autoclave, press, or vacuum bag techniques, but usage is not limited to such applications. This product is not intended for use in applications requiring flame or fire resistance.