Abstract: A collectible structure of delicate frangible hollow construction having a circular or other shaped opening in its rear wall is provided with a relatively axially short protective sleeve of tough composition fitting within the opening and retained therein, e. g. by frictional engagement with the opening edges. An illuminating unit having a light source for illuminating the collectible structure from its interior is placed within the sleeve with the light source disposed within the structure interior beyond the inner end of the sleeve. Attached to the unit are resilient spring supporting means therefor, preferably in the form of plural resilient outwardly-directed fingers, in engagement with an interior surface of the sleeve so that the sleeve surface bears the force of the supporting means. Preferably, the sleeve has a short arcuate segment removed from its perimeter to permit the sleeve to be compressed to fit different sized openings.