Ceiling insert

A ceiling insert in combination with a supplemental base member for locating the insert on a ceiling board while the insert is cast in concrete, the insert comprising an outer cylinder body having an upper hole of large diameter, a central hole below said upper hole having a taper such that the diameter of the central hole decreases downwardly away from the upper hole and having a step portion at a bottom end of the central hole, a straight lower hole below the step portion having a smooth inner surface and having a diameter less than the diameter of the bottom end of the central hole, said lower hole extending from the step portion through a lower end of the insert, a tapered split nut installed in the central hole of said outer cylinder body, a coil spring installed in the upper hole above the split nut, and a lid body as a cover fixed to a top end face of the outer cylinder body, wherein the coil spring is compressed by the lid body and the split nut and the split nut is urged downward by the coil spring against the step portion of the central hole, the supplemental base member comprising a continuous outer ring and a central tube defining an annular space therebetween for removably engaging a lower end of the insert with said central tube extending into the lower hole of the insert, the supplemental base member further including a screw extending downwardly within the central tube for securing the supplemental base member to the ceiling board.