Abstract: A connector assembly for use in aggregate structures cast over a form has a connector socket body embedded in the structure, the body having a threaded bore therein. An elongated locking member extends through a hole in the form and is threadedly engaged in the bore and has a lower section with a sleeve thereon. Projecting from the sleeve are a plurality of resilient splines which extend angularly outward from the sleeve in the direction of the socket body for engagement against the form to lock the socket body in place during solidification of the aggregate thereabout.