Abstract: A chuck including a body having a tail section and a nose section defining an axial bore. A plurality of jaws are movably disposed with respect to the axial bore and a nut is in threaded engagement with the jaws. A sleeve engages the nut so that rotation of the sleeve moves the jaws. A first ring defines a plurality of teeth and a second ring is rotatable relative to the nut over a limited arc and defines at least one pawl. In a first state, the second ring is non-rotatable relative to the first ring in both the opening and closing directions, and in a second state the first and second rings are rotatable about the body, and the second ring is rotatable relative to the first ring in the closing direction.