It is composite tube produced from a medium weave glass fabric reinforcement combined with an epoxy resin system. RT520M meets the requirements of MIL-I-24768/2, Type GEE. RT520 is designed for demanding electrical and mechanical applications, including cams, rings, collars, inserts, bushings, cryogenic beakers, flasks or tanks, spacers, insulators, timing wheels, neck tubes, rotor sleeves, laser housings, light duty gears, and fluid and gas transfer.