Sample spool of a 4-ply yarn of untwisted fiberglas fibers made by Owens-Corning Glass Co., Toledo, Ohio. Used in the defense industry during World War II. One of several products used in manufacture of the tail-wheel boot for a P-47 Thunderbolt fighter airplane, made by Campbell Products Co., Greensboro Kentucky, who donated samples of the materials and a section of the boot. (T.09101-T09104)