resistance this type of glass is the most widely used in fibers for reinforcing plastics s glass is the higher strength and higher cost material relative to e glass s glass is a magnesia alumina silicate glass for aerospace applications with high tensile strength originally u201c s u201d stood for high strength e glass fiber may be incorporated in the composite in a wide range of fiber weights and thermoplastic polymer matrix material the e glass may range from about 10 to about 40 ounces per square yard oz sq yd for example 19 to 30 or in a particular embodiment 21 4 to 28 4 oz sq yd other fibers may also be incorporated optionally in combination with e glass and or s glass such other fibers include ecr a and c glass as well as other glass fibers fibers formed from quartz magnesia aluminosilicate non alkaline aluminoborosilicate soda borosilicate soda silicate soda lime aluminosilicate lead silicate non alkaline lead boroalumina non alkaline barium boroalumina non alkaline zinc boroalumina non alkaline iron aluminosilicate cadmium borate alumina fibers asbestos boron silicone carbide graphite and carbon such as those derived from the carbonization of polyethylene polyvinylalcohol saran aramid polyamide polybenzimidazole polyoxadiazole polyphenylene ppr petroleum and coal pitches isotropic mesophase pitch cellulose and polyacrylonitrile ceramic fibers metal fibers as for example steel aluminum metal alloys and the like.