Abstract: The fastener of the present invention has a head integrally formed with a threaded shank. The face of the head has a triangular recess with a triangular centerpost extending upward from the recess. The recess has three sides forming corners, and the centerpost has three sides forming apices. The walls of the recess and the walls of the centerpost may form a channel therebetween and the top of the centerpost may be flush with the face of the head. The corners and the apices may be rounded to provide stress relief and to facilitate tool insertion and removal. The periphery of the head may be provided with a conical side wall narrowing toward the shank so that the fastener may be countersunk. The shank may be completely threaded or only partially threaded, and may have a pointed or chamfered end. It also may be provided with a hole so that a retaining device may be inserted therethrough.