Abstract: A stability unit used in combination with a three ring binder of the type having front and back covers hingedly mounted between a spine. A binder assembly including arcuate rings halves is mounted to either the spine or cover. The stability unit is mounted to either a spine, cover or both. The stability unit includes recesses adjacent each ring halve and is constructed and arranged such that a ring halve may be inserted therewithin past a resilient projection which provides a locking function. When locked, the binder may be positioned in an upright attitude.

Abstract: A data binder having compression bars forming longitudinal rails and a center channel, flexible posts securing data sheets between compression bars and a retaining slide member embracing the rails to hold the bent over posts in place. Each end of said retaining slide member includes a flare at the end of the center groove for receiving the post. The guide groove facilitates insertion of the post into the retaining slide member.