Strongwell Fibrebolt FN.38 Fiberglass Molded Nut, 3/8". Corrosion resistant, easy to fabricate, low maintenance, low in conductivity, transparent to electromagnetic waves and the color blends with most structural materials. For use with SGW-STD.38 fiberglass stud. NOTE: Fastener assembly does not possess the thread shear strength of steel, but has sufficient strength to be a viable alternative in structures where fastener corrosion is a concern or where metal fasteners are not permitted (antennae housings, computer equipment testing structures, etc.).