Abstract: A shaft has a head attached at one end and terminates at the other end in a tapered tip. A slot passes through the shaft, extending from the end opposite the head at least partially along the length of the shaft. Helical thread segments extend along the shaft, matching the thread in the threaded hole. The screw is inserted by pushing it into the threaded hole; the shaft halves are compressed together until the outer diameter of the thread segments on the shaft is smaller than the inner diameter of the threads in the threaded hole. The shaft halves spring back to their uncompressed position after insertion. The thread segments on the shaft mesh with the thread in the hole, retaining the shaft in the hole after insertion. The shaft must be removed by unscrewing the shaft.