A chuck assembly for a rotary power tool, the chuck assembly comprising: a chuck body rotatable about a central axis , the chuck body including a plurality of slots and a first plurality of thread segments , each of the slots oriented at an oblique angle relative to the central axis ; a plurality of jaws , each of the jaws movable along a respective one of the slots ; and a collar coupled to the plurality of jaws , wherein the collar is rotatable relative to the chuck body and the plurality of jaws is moveable along the plurality of slots in response to rotation of the collar , the chuck assembly being characterized in that : the collar includes a second plurality of thread segments , the collar is rotatable relative to the chuck body to selectively engage at least one of the first plurality of thread segments with at least one of the second plurality of thread segments , the plurality of jaws is movable along the plurality of slots in response to rotation of the collar when the at least one of the first plurality of thread segments is engaged with the at least one of the second plurality of thread segments , the collar is rotatable relative to the chuck body to selectively align the second plurality of thread segments with the plurality of slots , and the plurality of jaws is moveable along the plurality of slots in response to sliding the collar along the chuck body when the second plurality of thread segments is aligned with the plurality of slots . a chuck body rotatable about a central axis , the chuck body including a plurality of slots and a first plurality of thread segments , each of the slots oriented at an oblique angle relative to the central axis ; a plurality of jaws , each of the jaws movable along a respective one of the slots ; and a collar coupled to the plurality of jaws , wherein the collar is rotatable relative to the chuck body and the plurality of jaws is moveable along the plurality of slots in response to rotation of the collar , the chuck assembly being characterized in that : the collar includes a second plurality of thread segments , the collar is rotatable relative to the chuck body to selectively engage at least one of the first plurality of thread segments with at least one of the second plurality of thread segments , the plurality of jaws is movable along the plurality of slots in response to rotation of the collar when the at least one of the first plurality of thread segments is engaged with the at least one of the second plurality of thread segments , the collar is rotatable relative to the chuck body to selectively align the second plurality of thread segments with the plurality of slots , and the plurality of jaws is moveable along the plurality of slots in response to sliding the collar along the chuck body when the second plurality of thread segments is aligned with the plurality of slots . the collar includes a second plurality of thread segments , the collar is rotatable relative to the chuck body to selectively engage at least one of the first plurality of thread segments with at least one of the second plurality of thread segments , the plurality of jaws is movable along the plurality of slots in response to rotation of the collar when the at least one of the first plurality of thread segments is engaged with the at least one of the second plurality of thread segments , the collar is rotatable relative to the chuck body to selectively align the second plurality of thread segments with the plurality of slots , and the plurality of jaws is moveable along the plurality of slots in response to sliding the collar along the chuck body when the second plurality of thread segments is aligned with the plurality of slots . <EOS>