Abstract: The wings on one side of a slot for an arch wire have slanting, oblong openings to receive a pivotal side of a generally rectangular fastening. The fastening is pivotally mounted in the openings; the pivotal side slides inwardly within the openings to allow the opposite latching side of the fastening to be passed over opposite latching wings; and then the pivotal side slides outwardly to retain the latching side within hook-shaped inner surfaces of the latching wings. The ends of the fastening cross over and retain an arch wire in a slot intermediate the wings. Auxiliary springs to provide rotational force on torque may be integral parts of the fastening.