An apertured cover defines pin penetrable locations for temporarily posting notices, indicia, and the like. A pin receiving and gripping the substrate adjacent the back surface of the cover retains any pins penetrably engaging the apertures in the cover. A hard backing sheet disposed adjacent the rear face of the substrate protects the substrate. Folded panels of the cover retain the substrate and the backing sheet in fixed relationship with one another to form a unitary structure and protect the edges of the substrate.