Abstract: A hammer-in expansion fastener for embedding into a wall and receiving a screw having an elongated body which is provided with two opposite ends and a bore extending into it from one end to receive a screw. The other end of the body is tapered inwardly to a leading end of the body to an extent allowing the wall plug to be driven into a wall of building material. The other end is further provided with a non-uniform taper of: (a) between 12° to 18° to the longitudinal axis of the body at the leading end and about 10 mm in length measured along the longitudinal axis; and (b) from 4° to 8° to the longitudinal axis of the body at a portion remote from the leading end.