Abstract: An agricultural tool bar having a main beam and a pair of tool supporting side wings which fold forwardly from an extended operating position to a folded transport position. The inner ends of the wings are attached to hinges which are pivoted to a carriage mounted for rolling movement along the main beam. Hydraulic cylinders pivot the hinges relative to the carriage as diagonal links cause the carriage to roll along the beam in a manner to fold and unfold the side wings. Additional hydraulic cylinders act to raise the main beam to the transport position wherein the side wings are wholly supported on the main beam which is in turn supported on a wheel assembly having a sturdy axle underlying it.