Threaded fastener having a head with a triangle centerpost within a triangle recess

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