Also known as spun glass, fiberglass is a composite of extremely fine fibers of glass. Invented in 1938 by Russell Games Slayter of Owens-Corning for use as insulating material, the raw spun glass is used as a reinforcing agent and combined with polymers and epoxies to create what is known popularly as fiberglass, which can be drawn, shaped, and molded for a wide variety of uses. The low weight, great tensile strength, and dielectric properties of fiberglass contribute to its wide use in both rigid and nonrigid applications, including boat hulls, swimming pools, hot tubs, surfboards, thermal insulation, automobile bodies, and cable strength members. Owens-Corning remains the largest manufacturer of fiberglass, which it markets as Fiberglas