Positive Lock Ring Binder Mechanism

A ring binder mechanism includes a housing having longitudinal ends and a top surface, hinge plates supported by the housing for pivoting motion about a pivot axis relative to the housing, and rings for holding loose-leaf pages. Each ring includes first and second ring members. The first ring member is movable relative to the second ring member between closed and opened positions of the rings. A control structure is supported by the housing and movable relative to the housing. The control structure produces the pivoting motion of the hinge plates in at least one direction. The control structure has an actuating lever pivotally connected to the housing and disposed generally above the top surface of the housing. The actuating lever is formed for receiving a fastener therethrough for connecting the housing to a cover.