Abstract: An explosion venting wall structure incorporating a releasable fastener means. The fastener means comprises a fastener member having a substantially circular body with an opening therethrough, and at least two offset arms extended radially outward from said tubular body. The fastener member circular body is adapted to be disposed in a circular opening in a wall structure, with the offset arms overlapping the opening edge and seated against the wall surface, and with a screw or other retainer means provided for extension through the circular body opening and through said opening in the wall and into securing engagement with a building structural support member.