a one - piece molded plastic reusable internally threaded anchor nut removably insertable in a mounting hole in a workpiece and adapted to receive a screw comprises two sections which are joined together by an integrally formed web or hinge . when the sections are folded together , they define an internally threaded screw - receiving passage and an external releasable locking mechanism for securing the anchor nut in the mounting hole . in one embodiment the portions defining the screw - receiving passage are bifurcated and expand outwardly as the screw is inserted so as to cause the external locking mechanism to engage the edge of the mounting hole in which the nut was previously inserted . in other embodiments , the external locking mechanism operates independently of screw insertion and the anchor nut with the screw already disposed therein is insertable into or removable from the mounting hole when the projections are depressed .