Abstract: A quick coupling device for releasably connecting a boom arm to a tool, such as a material handling bucket, including a coupling frame adapted for connection to the boom and having wedge members provided on opposite, vertically extending sides thereof and projecting outwardly in a transverse direction from these sides. The wedge members engage in wedge-shaped channels formed by rigid connecting rails mounted on the top of the bucket. A hydraulic locking mechanism for securing the wedge members in the wedge-shaped channels is mounted at one end of the coupling frame and includes a hydraulic actuator and preferably two locking bars movable by this actuator between a locked position and an unlocked position. During use of this coupling device, in the locking position the two locking bars extend into cooperating openings provided on the connecting rails and thereby prevent the coupling device from detaching from the bucket.