A ring binder mechanism includes an elongate plate having a longitudinal axis. Hinge plates are supported by the plate for pivoting relative to the elongate plate. Ring members are mounted on the hinge plates and moveable between a closed position and an open position. A control structure is supported by the elongate plate and controllably pivots the hinge plates to move the ring members between the closed and open positions. The control structure has a travel bar connected to the hinge plates for moving the hinge plates between the closed and open positions. A spring biases the travel bar toward the closed position.