Abstract: An improved snap-in metal plug for closing either a flat or flanged opening in a sheet metal panel or the like. The plug, in one embodiment, includes a circular disc formed with three co-planar tongues extending radially outwardly from the plug principal axis, with each tongue disposed about a radial center line of symmetry. Each tongue terminates in a radially outer fold line, disposed normal to its associated center line, formed by an underlying reverse folded ply. The ply terminates in a radially inner right angle bend juncture from which projects a single downstanding finger defining opposite vertical side edges. Each side edge has an upper tang struck outwardly and upwardly therefrom defining an upper tang free end. Upon the plug being seated in a flat opening, each upper tang has its upper end locked, in a snap-in manner, juxtaposed the panel interior surface.