It (NEMA G-5) is a thermoset rolled and molded composite consisting of a medium-weave glass fabric reinforcement combined with a melamine resin system. RM505 complies with the requirements of MIL-I-24768/8, Type GMG and is designed for high electrical and mechanical strength, along with arc and flame resistance. RM505 is suitable for plugs, dowels, inserts, bushings, collars, spacers, and insulators in applications where the humidity is low, and should not be used when immersed in water.