Abstract: A plug or closure for closing and substantially sealing an aperture in a vehicle body panel. The plug comprises a plate portion and a resilient spring element carrying a plurality of resilient snap-engaging legs. The plate portion and the spring are separate and can be formed from different materials. The plate portion has an undersurface and one or more bosses in the undersurface defining a plurality of side walls. The spring has a body integral with the legs defining a plurality of edges and the spring is attached to the plate by forcing the body of the spring between or over the bosses or boss respectively so that the edges of the body of the spring frictionally engage the side walls of the boss or bosses. The plug may be provided with a ring of sealing material on the periphery of the undersurface of the plate.