Abstract: A ball lock assembly is provided which permits preconstruction of certain ones of the assembly components. Consequently, the assembly, in kit form, has few parts, and may be integrated simply in a final binder construction by a binder manufacturer. The lock assembly includes a ball lock device having a first and second end. The ball lock device has an axial opening through it. A first end of the ball lock device receives a post of a suitable loose leaf metal used in the manufacture of a complete binder while the second end is constructed to permit attachment of a pull ring. The lock device includes a lock extension having a ball container movably mounted in it. A retaining sleeve is positioned between an internal diameter of the lock extension and an external diameter of the ball container. The sleeve permits the preassembly of the various parts of the ball lock device so that the lock assembly may be sold in kit form.