Abstract: In a typewriter ribbon cartridge, it is necessary to maintain tension on the span of ribbon extending outside the cartridge to prevent tangling and to insure high print quality during machine operation. One technique for insuring that adequate tension is maintained is disclosed herein as an anti-backup back check device. Connected to the takeup spool of the ribbon cartridge is a disc member supporting thereon a pair of thin flexible resilient arms with outwardly oriented pointed ends. These ends formed in the shape of points engage ratchet teeth formed around the interior surface of a cylinder. The cylinder is formed as a part of the ribbon cartridge and, thus, is permanently positioned and fixed with respect to it. As the takeup spool disc and arms are rotated by the ribbon feed mechanism, the arms will flex and permit a rotation of the disc and takeup spool with a minimal drag force.