A drill chuck has a chuck body centered on an axis, made of plastic, and formed with an axially rearwardly open drive-spindle seat, at least one axially extending slot of ring-segment section opening radially inward into the seat, an axially forwardly open tool-holding cavity, and a plurality of angled jaw guides. Respective jaws are movable in the guides and engaged by a threaded ring axially fixed on the body and rotatable about the axis thereon. A tightening sleeve rotatable about the axis on the body is connected to the ring for rotating same.